From 2e6ba6c60a1328996c953d3694a2698c4b26dc75 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Fri, 14 May 2021 12:36:55 +0100
Subject: [PATCH 01/29] Implement `seal_debug_message`

---
 crates/engine/src/ext.rs                      |  8 ++--
 crates/engine/src/test_api.rs                 | 42 ++++++++--------
 crates/engine/src/tests.rs                    |  6 +--
 crates/env/src/api.rs                         |  6 +--
 crates/env/src/backend.rs                     | 11 ++++-
 .../engine/experimental_off_chain/impls.rs    |  4 +-
 .../engine/experimental_off_chain/test_api.rs |  8 ++--
 .../off_chain/db/{console.rs => debug_buf.rs} | 48 +++++++++----------
 crates/env/src/engine/off_chain/db/mod.rs     |  8 ++--
 crates/env/src/engine/off_chain/impls.rs      |  4 +-
 crates/env/src/engine/off_chain/mod.rs        | 12 ++---
 crates/env/src/engine/off_chain/test_api.rs   |  8 ++--
 crates/env/src/engine/on_chain/ext.rs         |  6 +--
 crates/env/src/engine/on_chain/impls.rs       |  4 +-
 crates/env/src/lib.rs                         | 21 ++++++++
 examples/contract-transfer/lib.rs             |  7 ++-
 16 files changed, 115 insertions(+), 88 deletions(-)
 rename crates/env/src/engine/off_chain/db/{console.rs => debug_buf.rs} (52%)

diff --git a/crates/engine/src/ext.rs b/crates/engine/src/ext.rs
index 8fa8f900f20..de50e1d0dfa 100644
--- a/crates/engine/src/ext.rs
+++ b/crates/engine/src/ext.rs
@@ -317,10 +317,10 @@ impl Engine {
         unimplemented!("off-chain environment does not yet support `restore_to`");
     }
 
-    /// Prints the given contents to the console log.
-    pub fn println(&mut self, content: &str) {
-        self.debug_info.record_println(String::from(content));
-        println!("{}", content);
+    /// Records the given debug message and appends to stdout.
+    pub fn debug_message(&mut self, message: &str) {
+        self.debug_info.record_debug_message(String::from(message));
+        print!("{}", message);
     }
 
     /// Conduct the BLAKE-2 256-bit hash and place the result into `output`.
diff --git a/crates/engine/src/test_api.rs b/crates/engine/src/test_api.rs
index 71d7b3e01c0..b3dd43a5b02 100644
--- a/crates/engine/src/test_api.rs
+++ b/crates/engine/src/test_api.rs
@@ -33,41 +33,41 @@ pub struct EmittedEvent {
 }
 
 #[derive(Clone)]
-pub struct RecordedPrintlns {
-    printlns: Vec<String>,
+pub struct RecordedDebugMessages {
+    debug_messages: Vec<String>,
 }
 
-impl RecordedPrintlns {
+impl RecordedDebugMessages {
     // Creates a new `Engine instance.
     pub fn new() -> Self {
         Self {
-            printlns: Vec::new(),
+            debug_messages: Vec::new(),
         }
     }
 
-    // Records a new println.
-    pub fn record(&mut self, println: String) {
-        self.printlns.push(println);
+    // Records a new debug message.
+    pub fn record(&mut self, message: String) {
+        self.debug_messages.push(message);
     }
 
-    // Clears all recorded printlns.
+    // Clears all recorded debug messages.
     pub fn clear(&mut self) {
-        self.printlns.clear();
+        self.debug_messages.clear();
     }
 }
 
-impl Default for RecordedPrintlns {
+impl Default for RecordedDebugMessages {
     fn default() -> Self {
         Self::new()
     }
 }
 
-impl IntoIterator for RecordedPrintlns {
+impl IntoIterator for RecordedDebugMessages {
     type Item = String;
     type IntoIter = std::vec::IntoIter<Self::Item>;
 
     fn into_iter(self) -> Self::IntoIter {
-        self.printlns.into_iter()
+        self.debug_messages.into_iter()
     }
 }
 
@@ -76,7 +76,7 @@ pub struct DebugInfo {
     /// Emitted events recorder.
     emitted_events: Vec<EmittedEvent>,
     /// Emitted print messages recorder.
-    emitted_printlns: RecordedPrintlns,
+    emitted_debug_messages: RecordedDebugMessages,
     /// The total number of reads to the storage.
     count_reads: HashMap<AccountId, usize>,
     /// The total number of writes to the storage.
@@ -96,7 +96,7 @@ impl DebugInfo {
     pub fn new() -> Self {
         Self {
             emitted_events: Vec::new(),
-            emitted_printlns: RecordedPrintlns::new(),
+            emitted_debug_messages: RecordedDebugMessages::new(),
             count_reads: HashMap::new(),
             count_writes: HashMap::new(),
             cells_per_account: HashMap::new(),
@@ -108,7 +108,7 @@ impl DebugInfo {
         self.count_reads.clear();
         self.count_writes.clear();
         self.emitted_events.clear();
-        self.emitted_printlns.clear();
+        self.emitted_debug_messages.clear();
         self.cells_per_account.clear();
     }
 
@@ -159,9 +159,9 @@ impl DebugInfo {
             .unwrap_or(None)
     }
 
-    /// Records a println.
-    pub fn record_println(&mut self, println: String) {
-        self.emitted_printlns.record(println);
+    /// Records a debug message.
+    pub fn record_debug_message(&mut self, message: String) {
+        self.emitted_debug_messages.record(message);
     }
 
     /// Records an event.
@@ -215,9 +215,9 @@ impl Engine {
         self.exec_context.callee()
     }
 
-    /// Returns the contents of the past performed environmental `println` in order.
-    pub fn get_recorded_printlns(&self) -> RecordedPrintlns {
-        self.debug_info.emitted_printlns.clone()
+    /// Returns the contents of the past performed environmental `debug_message` in order.
+    pub fn get_emitted_debug_messages(&self) -> RecordedDebugMessages {
+        self.debug_info.emitted_debug_messages.clone()
     }
 
     /// Returns the recorded emitted events in order.
diff --git a/crates/engine/src/tests.rs b/crates/engine/src/tests.rs
index ed83e455577..798f5287de7 100644
--- a/crates/engine/src/tests.rs
+++ b/crates/engine/src/tests.rs
@@ -115,10 +115,10 @@ fn transfer() {
 }
 
 #[test]
-fn printlns() {
+fn debug_messages() {
     let mut engine = Engine::new();
-    engine.println("foobar");
-    let mut recorded = engine.get_recorded_printlns().into_iter();
+    engine.debug_message("foobar");
+    let mut recorded = engine.get_emitted_debug_messages().into_iter();
     assert_eq!(recorded.next(), Some("foobar".into()));
     assert_eq!(recorded.next(), None);
 }
diff --git a/crates/env/src/api.rs b/crates/env/src/api.rs
index 3656a8ce21d..5e0df2679a2 100644
--- a/crates/env/src/api.rs
+++ b/crates/env/src/api.rs
@@ -511,10 +511,10 @@ where
     })
 }
 
-/// Prints the given contents to the environmental log.
-pub fn debug_println(content: &str) {
+/// Appends the given message to the debug message buffer.
+pub fn debug_message(message: &str) {
     <EnvInstance as OnInstance>::on_instance(|instance| {
-        EnvBackend::println(instance, content)
+        EnvBackend::debug_message(instance, message)
     })
 }
 
diff --git a/crates/env/src/backend.rs b/crates/env/src/backend.rs
index f3d3b588822..19f6a85d9e8 100644
--- a/crates/env/src/backend.rs
+++ b/crates/env/src/backend.rs
@@ -115,8 +115,15 @@ pub trait EnvBackend {
     where
         R: scale::Encode;
 
-    /// Prints the given contents to the console log.
-    fn println(&mut self, content: &str);
+    /// Emit a custom debug message.
+    ///
+    /// The message is appended to the debug buffer which is then supplied to the calling RPC
+    /// client. This buffer is also printed as a debug message to the node console if the
+    /// `debug` log level is enabled for the `runtime::contracts` target.
+    ///
+    /// This is a no-op if debug message recording is disabled which is always the case
+    /// when the code is executing on-chain.
+    fn debug_message(&mut self, content: &str);
 
     /// Conducts the crypto hash of the given input and stores the result in `output`.
     fn hash_bytes<H>(&mut self, input: &[u8], output: &mut <H as HashOutput>::Type)
diff --git a/crates/env/src/engine/experimental_off_chain/impls.rs b/crates/env/src/engine/experimental_off_chain/impls.rs
index a1a254e8bbf..1ce60f8bd8b 100644
--- a/crates/env/src/engine/experimental_off_chain/impls.rs
+++ b/crates/env/src/engine/experimental_off_chain/impls.rs
@@ -225,8 +225,8 @@ impl EnvBackend for EnvInstance {
         )
     }
 
-    fn println(&mut self, content: &str) {
-        self.engine.println(content)
+    fn debug_message(&mut self, message: &str) {
+        self.engine.debug_message(message)
     }
 
     fn hash_bytes<H>(&mut self, input: &[u8], output: &mut <H as HashOutput>::Type)
diff --git a/crates/env/src/engine/experimental_off_chain/test_api.rs b/crates/env/src/engine/experimental_off_chain/test_api.rs
index 8608270cbe6..e44c9a5d238 100644
--- a/crates/env/src/engine/experimental_off_chain/test_api.rs
+++ b/crates/env/src/engine/experimental_off_chain/test_api.rs
@@ -23,7 +23,7 @@ use crate::{
     Result,
 };
 use core::fmt::Debug;
-use ink_engine::test_api::RecordedPrintlns;
+use ink_engine::test_api::RecordedDebugMessages;
 use std::panic::UnwindSafe;
 
 /// Record for an emitted event.
@@ -129,10 +129,10 @@ where
     unimplemented!("off-chain environment does not yet support `set_block_entropy`");
 }
 
-/// Returns the contents of the past performed environmental `println` in order.
-pub fn recorded_printlns() -> RecordedPrintlns {
+/// Returns the contents of the past performed environmental debug messages in order.
+pub fn recorded_debug_messages() -> RecordedDebugMessages {
     <EnvInstance as OnInstance>::on_instance(|instance| {
-        instance.engine.get_recorded_printlns()
+        instance.engine.get_emitted_debug_messages()
     })
 }
 
diff --git a/crates/env/src/engine/off_chain/db/console.rs b/crates/env/src/engine/off_chain/db/debug_buf.rs
similarity index 52%
rename from crates/env/src/engine/off_chain/db/console.rs
rename to crates/env/src/engine/off_chain/db/debug_buf.rs
index 67486b4e8f4..8bdcbbcd075 100644
--- a/crates/env/src/engine/off_chain/db/console.rs
+++ b/crates/env/src/engine/off_chain/db/debug_buf.rs
@@ -14,53 +14,53 @@
 
 use ink_prelude::string::String;
 
-/// A debug console used to print console contents and store them.
-pub struct Console {
-    /// The buffer to store the already pasted contents.
-    past_prints: Vec<String>,
+/// A debug buffer used to store debug messages and print them to stdout.
+pub struct DebugBuffer {
+    /// The buffer to store the emitted debug messages.
+    past_debug_messages: Vec<String>,
 }
 
-impl Console {
+impl DebugBuffer {
     /// Creates a new empty console.
     pub fn new() -> Self {
         Self {
-            past_prints: Vec::new(),
+            past_debug_messages: Vec::new(),
         }
     }
 
-    /// Resets the console to uninitialized state.
+    /// Resets the debug buffer to uninitialized state.
     pub fn reset(&mut self) {
-        self.past_prints.clear();
+        self.past_debug_messages.clear();
     }
 
-    /// Prints the contents to the actual console and stores them.
-    pub fn println(&mut self, contents: &str) {
-        self.past_prints.push(contents.to_string());
-        println!("{}", contents);
+    /// Prints the message to stdout and stores it.
+    pub fn debug_message(&mut self, message: &str) {
+        self.past_debug_messages.push(message.to_string());
+        print!("{}", message);
     }
 
-    /// Returns an iterator over the past console prints.
-    pub fn past_prints(&self) -> PastPrints {
-        PastPrints::new(self)
+    /// Returns an iterator over the past debug messages.
+    pub fn past_debug_messages(&self) -> DebugMessages {
+        DebugMessages::new(self)
     }
 }
 
-/// Iterator over the past prints to the console.
-pub struct PastPrints<'a> {
+/// Iterator over the past debug messages.
+pub struct DebugMessages<'a> {
     /// Iterator over the past printlns.
     iter: core::slice::Iter<'a, String>,
 }
 
-impl<'a> PastPrints<'a> {
-    /// Creates a new iterator over the past console prints.
-    fn new(console: &'a Console) -> Self {
+impl<'a> DebugMessages<'a> {
+    /// Creates a new iterator over the past debug messages.
+    fn new(console: &'a DebugBuffer) -> Self {
         Self {
-            iter: console.past_prints.iter(),
+            iter: console.past_debug_messages.iter(),
         }
     }
 }
 
-impl<'a> Iterator for PastPrints<'a> {
+impl<'a> Iterator for DebugMessages<'a> {
     type Item = &'a str;
 
     fn next(&mut self) -> Option<Self::Item> {
@@ -68,13 +68,13 @@ impl<'a> Iterator for PastPrints<'a> {
     }
 }
 
-impl<'a> ExactSizeIterator for PastPrints<'a> {
+impl<'a> ExactSizeIterator for DebugMessages<'a> {
     fn len(&self) -> usize {
         self.iter.len()
     }
 }
 
-impl<'a> DoubleEndedIterator for PastPrints<'a> {
+impl<'a> DoubleEndedIterator for DebugMessages<'a> {
     fn next_back(&mut self) -> Option<Self::Item> {
         self.iter.next_back().map(AsRef::as_ref)
     }
diff --git a/crates/env/src/engine/off_chain/db/mod.rs b/crates/env/src/engine/off_chain/db/mod.rs
index 100a652127e..42ff658b6ab 100644
--- a/crates/env/src/engine/off_chain/db/mod.rs
+++ b/crates/env/src/engine/off_chain/db/mod.rs
@@ -15,7 +15,7 @@
 mod accounts;
 mod block;
 mod chain_spec;
-mod console;
+mod debug_buf;
 mod events;
 mod exec_context;
 
@@ -30,9 +30,9 @@ pub use self::{
     },
     block::Block,
     chain_spec::ChainSpec,
-    console::{
-        Console,
-        PastPrints,
+    debug_buf::{
+        DebugBuffer,
+        DebugMessages,
     },
     events::{
         EmittedEvent,
diff --git a/crates/env/src/engine/off_chain/impls.rs b/crates/env/src/engine/off_chain/impls.rs
index 1b20f9d51e2..3ae92b99a1c 100644
--- a/crates/env/src/engine/off_chain/impls.rs
+++ b/crates/env/src/engine/off_chain/impls.rs
@@ -171,8 +171,8 @@ impl EnvBackend for EnvInstance {
         std::process::exit(flags.into_u32() as i32)
     }
 
-    fn println(&mut self, content: &str) {
-        self.console.println(content)
+    fn debug_message(&mut self, message: &str) {
+        self.debug_buf.debug_message(message)
     }
 
     fn hash_bytes<H>(&mut self, input: &[u8], output: &mut <H as HashOutput>::Type)
diff --git a/crates/env/src/engine/off_chain/mod.rs b/crates/env/src/engine/off_chain/mod.rs
index 5dc11e5a0d5..d6a4cb43deb 100644
--- a/crates/env/src/engine/off_chain/mod.rs
+++ b/crates/env/src/engine/off_chain/mod.rs
@@ -29,7 +29,7 @@ pub use self::{
     db::{
         AccountError,
         EmittedEvent,
-        PastPrints,
+        DebugMessages,
     },
     typed_encoded::TypedEncodedError,
 };
@@ -40,7 +40,7 @@ use self::{
         AccountsDb,
         Block,
         ChainSpec,
-        Console,
+        DebugBuffer,
         EmittedEventsRecorder,
         ExecContext,
     },
@@ -84,8 +84,8 @@ pub struct EnvInstance {
     chain_spec: ChainSpec,
     /// The blocks of the chain.
     blocks: Vec<Block>,
-    /// The console to print debug contents.
-    console: Console,
+    /// The debug buffer to collect debug messages and print them to stdout.
+    debug_buf: DebugBuffer,
     /// Handler for registered chain extensions.
     chain_extension_handler: ChainExtensionHandler,
     /// Emitted events recorder.
@@ -102,7 +102,7 @@ impl EnvInstance {
             exec_context: Vec::new(),
             chain_spec: ChainSpec::uninitialized(),
             blocks: Vec::new(),
-            console: Console::new(),
+            debug_buf: DebugBuffer::new(),
             chain_extension_handler: ChainExtensionHandler::new(),
             emitted_events: EmittedEventsRecorder::new(),
             clear_storage_disabled: false,
@@ -133,7 +133,7 @@ impl EnvInstance {
         self.exec_context.clear();
         self.chain_spec.reset();
         self.blocks.clear();
-        self.console.reset();
+        self.debug_buf.reset();
         self.chain_extension_handler.reset();
         self.emitted_events.reset();
         self.clear_storage_disabled = false;
diff --git a/crates/env/src/engine/off_chain/test_api.rs b/crates/env/src/engine/off_chain/test_api.rs
index 855be01a29c..41c979b9d53 100644
--- a/crates/env/src/engine/off_chain/test_api.rs
+++ b/crates/env/src/engine/off_chain/test_api.rs
@@ -215,8 +215,8 @@ where
     Ok(())
 }
 
-/// Returns the contents of the past performed environmental `println` in order.
-pub fn recorded_printlns() -> impl Iterator<Item = String> {
+/// Returns the contents of the past performed environmental debug messages in order.
+pub fn recorded_debug_messages() -> impl Iterator<Item = String> {
     <EnvInstance as OnInstance>::on_instance(|instance| {
         // We return a clone of the recorded strings instead of
         // references to them since this would require the whole `on_instance`
@@ -224,8 +224,8 @@ pub fn recorded_printlns() -> impl Iterator<Item = String> {
         // ultimately allow leaking those `'static` references to the outside
         // and potentially lead to terrible bugs such as iterator invalidation.
         instance
-            .console
-            .past_prints()
+            .debug_buf
+            .past_debug_messages()
             .map(ToOwned::to_owned)
             .collect::<Vec<_>>()
             .into_iter()
diff --git a/crates/env/src/engine/on_chain/ext.rs b/crates/env/src/engine/on_chain/ext.rs
index 5458d9e5591..49605952506 100644
--- a/crates/env/src/engine/on_chain/ext.rs
+++ b/crates/env/src/engine/on_chain/ext.rs
@@ -308,7 +308,7 @@ mod sys {
 
         pub fn seal_set_rent_allowance(value_ptr: Ptr32<[u8]>, value_len: u32);
 
-        pub fn seal_println(str_ptr: Ptr32<[u8]>, str_len: u32);
+        pub fn seal_debug_message(str_ptr: Ptr32<[u8]>, str_len: u32);
 
         pub fn seal_hash_keccak_256(
             input_ptr: Ptr32<[u8]>,
@@ -604,9 +604,9 @@ pub fn random(subject: &[u8], output: &mut &mut [u8]) {
     extract_from_slice(output, output_len as usize);
 }
 
-pub fn println(content: &str) {
+pub fn debug_message(content: &str) {
     let bytes = content.as_bytes();
-    unsafe { sys::seal_println(Ptr32::from_slice(bytes), bytes.len() as u32) }
+    unsafe { sys::seal_debug_message(Ptr32::from_slice(bytes), bytes.len() as u32) }
 }
 
 macro_rules! impl_hash_fn {
diff --git a/crates/env/src/engine/on_chain/impls.rs b/crates/env/src/engine/on_chain/impls.rs
index 48282af1cc3..ef951513721 100644
--- a/crates/env/src/engine/on_chain/impls.rs
+++ b/crates/env/src/engine/on_chain/impls.rs
@@ -251,8 +251,8 @@ impl EnvBackend for EnvInstance {
         ext::return_value(flags, enc_return_value);
     }
 
-    fn println(&mut self, content: &str) {
-        ext::println(content)
+    fn debug_message(&mut self, content: &str) {
+        ext::debug_message(content)
     }
 
     fn hash_bytes<H>(&mut self, input: &[u8], output: &mut <H as HashOutput>::Type)
diff --git a/crates/env/src/lib.rs b/crates/env/src/lib.rs
index 273e0812172..14dc8f0591f 100644
--- a/crates/env/src/lib.rs
+++ b/crates/env/src/lib.rs
@@ -99,3 +99,24 @@ pub use self::{
         NoChainExtension,
     },
 };
+pub use ink_prelude;
+
+/// Appends a formatted string to the `debug_message` buffer which will be:
+///  - Returned to the caller when the contract is invoked via RPC (*not* via an extrinsic)
+///  - Logged as a `debug!` message on the substrate node, which will be printed to the node
+///    console's `stdout` when the log level is set to `debug`.
+#[macro_export]
+macro_rules! debug_print {
+    ($($arg:tt)*) => ($crate::debug_message($crate::ink_prelude::format!($($arg)*)));
+}
+
+/// Appends a formatted string to the `debug_message` buffer, as per [`debug_print`] but
+/// with a newline appended.
+#[macro_export]
+macro_rules! debug_println {
+    () => ($crate::print!("\n"));
+    ($($arg:tt)*) => ({
+        $crate::debug_print!($($arg)*);
+        $crate::debug_print!("\n");
+    })
+}
diff --git a/examples/contract-transfer/lib.rs b/examples/contract-transfer/lib.rs
index f705e3ca63c..0b101b09daa 100644
--- a/examples/contract-transfer/lib.rs
+++ b/examples/contract-transfer/lib.rs
@@ -58,8 +58,8 @@ pub mod give_me {
         /// - Panics in case the transfer failed for another reason.
         #[ink(message)]
         pub fn give_me(&mut self, value: Balance) {
-            ink_env::debug_println(&ink_prelude::format!("requested value: {}", value));
-            ink_env::debug_println(&ink_prelude::format!(
+            ink_env::debug_println!("requested value: {}", value);
+            ink_env::debug_println!(
                 "contract balance: {}",
                 self.env().balance()
             ));
@@ -88,11 +88,10 @@ pub mod give_me {
         /// allowed to receive value as part of the call.
         #[ink(message, payable, selector = "0xCAFEBABE")]
         pub fn was_it_ten(&self) {
-            let msg = ink_prelude::format!(
+            ink_env::debug_println!(
                 "received payment: {}",
                 self.env().transferred_balance()
             );
-            ink_env::debug_println(&msg);
             assert!(
                 self.env().transferred_balance() == 10,
                 "payment was not ten"

From fa0fd9e3165710e633867bfa7f61efbc3ca2001f Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Fri, 14 May 2021 12:43:37 +0100
Subject: [PATCH 02/29] Update docs

---
 crates/env/src/engine/off_chain/db/debug_buf.rs | 2 +-
 crates/lang/macro/src/lib.rs                    | 8 +++-----
 2 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/crates/env/src/engine/off_chain/db/debug_buf.rs b/crates/env/src/engine/off_chain/db/debug_buf.rs
index 8bdcbbcd075..959c4d7365c 100644
--- a/crates/env/src/engine/off_chain/db/debug_buf.rs
+++ b/crates/env/src/engine/off_chain/db/debug_buf.rs
@@ -47,7 +47,7 @@ impl DebugBuffer {
 
 /// Iterator over the past debug messages.
 pub struct DebugMessages<'a> {
-    /// Iterator over the past printlns.
+    /// Iterator over the past debug messages.
     iter: core::slice::Iter<'a, String>,
 }
 
diff --git a/crates/lang/macro/src/lib.rs b/crates/lang/macro/src/lib.rs
index 65c41916a08..6f307389fe5 100644
--- a/crates/lang/macro/src/lib.rs
+++ b/crates/lang/macro/src/lib.rs
@@ -397,7 +397,7 @@ use proc_macro::TokenStream;
 /// #
 /// #[ink::contract]
 /// mod greeter {
-///     use ink_prelude::format;
+///     use ink_env::debug_println;
 ///
 ///     #[ink(storage)]
 ///     pub struct Greeter;
@@ -406,8 +406,7 @@ use proc_macro::TokenStream;
 ///         #[ink(constructor)]
 ///         pub fn new() -> Self {
 ///             let caller = Self::env().caller();
-///             let message = format!("thanks for instantiation {:?}", caller);
-///             ink_env::debug_println(&message);
+///             debug_println!("thanks for instantiation {:?}", caller);
 ///             Greeter {}
 ///         }
 ///
@@ -415,8 +414,7 @@ use proc_macro::TokenStream;
 ///         pub fn fund(&self) {
 ///             let caller = self.env().caller();
 ///             let value = self.env().transferred_balance();
-///             let message = format!("thanks for the funding of {:?} from {:?}", value, caller);
-///             ink_env::debug_println(&message);
+///             debug_println!("thanks for the funding of {:?} from {:?}", value, caller);
 ///         }
 ///     }
 /// }

From 8e896b31e1505ca89f39fa569bc5308955ed6654 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Fri, 14 May 2021 12:51:26 +0100
Subject: [PATCH 03/29] Fmt

---
 crates/env/src/engine/off_chain/mod.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crates/env/src/engine/off_chain/mod.rs b/crates/env/src/engine/off_chain/mod.rs
index d6a4cb43deb..bb3ce8d41b6 100644
--- a/crates/env/src/engine/off_chain/mod.rs
+++ b/crates/env/src/engine/off_chain/mod.rs
@@ -28,8 +28,8 @@ pub use self::{
     call_data::CallData,
     db::{
         AccountError,
-        EmittedEvent,
         DebugMessages,
+        EmittedEvent,
     },
     typed_encoded::TypedEncodedError,
 };

From 8738b80627ba7c74498f50f0d29f5179c416efda Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Wed, 19 May 2021 13:54:25 +0100
Subject: [PATCH 04/29] Fix debug_print macro

---
 crates/env/src/lib.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crates/env/src/lib.rs b/crates/env/src/lib.rs
index 14dc8f0591f..7a315deec72 100644
--- a/crates/env/src/lib.rs
+++ b/crates/env/src/lib.rs
@@ -107,7 +107,7 @@ pub use ink_prelude;
 ///    console's `stdout` when the log level is set to `debug`.
 #[macro_export]
 macro_rules! debug_print {
-    ($($arg:tt)*) => ($crate::debug_message($crate::ink_prelude::format!($($arg)*)));
+    ($($arg:tt)*) => ($crate::debug_message(&$crate::ink_prelude::format!($($arg)*)));
 }
 
 /// Appends a formatted string to the `debug_message` buffer, as per [`debug_print`] but

From 13e485e8d457adfc45eef7161fa938a7e6eab227 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Wed, 19 May 2021 17:11:34 +0100
Subject: [PATCH 05/29] review: use newline char

Co-authored-by: Robin Freyler <robin.freyler@gmail.com>
---
 crates/env/src/lib.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crates/env/src/lib.rs b/crates/env/src/lib.rs
index 7a315deec72..0ff13eddbfd 100644
--- a/crates/env/src/lib.rs
+++ b/crates/env/src/lib.rs
@@ -117,6 +117,6 @@ macro_rules! debug_println {
     () => ($crate::print!("\n"));
     ($($arg:tt)*) => ({
         $crate::debug_print!($($arg)*);
-        $crate::debug_print!("\n");
+        $crate::debug_print!('\n');
     })
 }

From 23011797cf2d8b50c214e487fc01f380ba227707 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Wed, 19 May 2021 17:28:37 +0100
Subject: [PATCH 06/29] Fix example

---
 examples/contract-transfer/lib.rs | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/examples/contract-transfer/lib.rs b/examples/contract-transfer/lib.rs
index 0b101b09daa..0547e4788f9 100644
--- a/examples/contract-transfer/lib.rs
+++ b/examples/contract-transfer/lib.rs
@@ -62,7 +62,7 @@ pub mod give_me {
             ink_env::debug_println!(
                 "contract balance: {}",
                 self.env().balance()
-            ));
+            );
 
             assert!(value <= self.env().balance(), "insufficient funds!");
 
@@ -341,8 +341,7 @@ pub mod give_me {
             ink_env::test::set_caller::<ink_env::DefaultEnvironment>(sender);
         }
 
-        fn default_accounts(
-        ) -> ink_env::test::DefaultAccounts<ink_env::DefaultEnvironment> {
+        fn default_accounts() -> ink_env::test::DefaultAccounts<ink_env::DefaultEnvironment> {
             ink_env::test::default_accounts::<ink_env::DefaultEnvironment>()
         }
 

From 5e091c1b6e93232c236225535a4ed52abc0e02c3 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Thu, 20 May 2021 09:41:59 +0100
Subject: [PATCH 07/29] Revert to newline string

---
 crates/env/src/lib.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crates/env/src/lib.rs b/crates/env/src/lib.rs
index 0ff13eddbfd..7a315deec72 100644
--- a/crates/env/src/lib.rs
+++ b/crates/env/src/lib.rs
@@ -117,6 +117,6 @@ macro_rules! debug_println {
     () => ($crate::print!("\n"));
     ($($arg:tt)*) => ({
         $crate::debug_print!($($arg)*);
-        $crate::debug_print!('\n');
+        $crate::debug_print!("\n");
     })
 }

From 2279a6f897a628811e421cca2ff80506ebefe913 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Thu, 20 May 2021 10:00:26 +0100
Subject: [PATCH 08/29] Fmt

---
 examples/contract-transfer/lib.rs | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/examples/contract-transfer/lib.rs b/examples/contract-transfer/lib.rs
index 0547e4788f9..097b204ec5f 100644
--- a/examples/contract-transfer/lib.rs
+++ b/examples/contract-transfer/lib.rs
@@ -59,10 +59,7 @@ pub mod give_me {
         #[ink(message)]
         pub fn give_me(&mut self, value: Balance) {
             ink_env::debug_println!("requested value: {}", value);
-            ink_env::debug_println!(
-                "contract balance: {}",
-                self.env().balance()
-            );
+            ink_env::debug_println!("contract balance: {}", self.env().balance());
 
             assert!(value <= self.env().balance(), "insufficient funds!");
 
@@ -341,7 +338,8 @@ pub mod give_me {
             ink_env::test::set_caller::<ink_env::DefaultEnvironment>(sender);
         }
 
-        fn default_accounts() -> ink_env::test::DefaultAccounts<ink_env::DefaultEnvironment> {
+        fn default_accounts(
+        ) -> ink_env::test::DefaultAccounts<ink_env::DefaultEnvironment> {
             ink_env::test::default_accounts::<ink_env::DefaultEnvironment>()
         }
 

From 9b7b68719d915f0f37ea5b3f5ad7352e08d46912 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Thu, 20 May 2021 11:14:41 +0100
Subject: [PATCH 09/29] Single call to debug_print for debug_println!

---
 crates/env/src/lib.rs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/crates/env/src/lib.rs b/crates/env/src/lib.rs
index 7a315deec72..52e4b998da9 100644
--- a/crates/env/src/lib.rs
+++ b/crates/env/src/lib.rs
@@ -114,9 +114,9 @@ macro_rules! debug_print {
 /// with a newline appended.
 #[macro_export]
 macro_rules! debug_println {
-    () => ($crate::print!("\n"));
+    () => ($crate::debug_print!("\n"));
     ($($arg:tt)*) => ({
-        $crate::debug_print!($($arg)*);
-        $crate::debug_print!("\n");
+        let msg = $crate::ink_prelude::format!($($arg)*);
+        $crate::debug_print!("{}\n", msg);
     })
 }

From c2b656c50aeb2c01ba0eb0d31a27d7f7a25cfec1 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Thu, 20 May 2021 12:05:15 +0100
Subject: [PATCH 10/29] Add missing ReturnCode, still need to handle it

---
 crates/env/src/engine/on_chain/ext.rs | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/crates/env/src/engine/on_chain/ext.rs b/crates/env/src/engine/on_chain/ext.rs
index 49605952506..2d784930bc3 100644
--- a/crates/env/src/engine/on_chain/ext.rs
+++ b/crates/env/src/engine/on_chain/ext.rs
@@ -308,7 +308,7 @@ mod sys {
 
         pub fn seal_set_rent_allowance(value_ptr: Ptr32<[u8]>, value_len: u32);
 
-        pub fn seal_debug_message(str_ptr: Ptr32<[u8]>, str_len: u32);
+        pub fn seal_debug_message(str_ptr: Ptr32<[u8]>, str_len: u32) -> ReturnCode;
 
         pub fn seal_hash_keccak_256(
             input_ptr: Ptr32<[u8]>,
@@ -606,7 +606,10 @@ pub fn random(subject: &[u8], output: &mut &mut [u8]) {
 
 pub fn debug_message(content: &str) {
     let bytes = content.as_bytes();
-    unsafe { sys::seal_debug_message(Ptr32::from_slice(bytes), bytes.len() as u32) }
+    // todo: handle return code
+    let _ret_code = unsafe {
+        sys::seal_debug_message(Ptr32::from_slice(bytes), bytes.len() as u32)
+    };
 }
 
 macro_rules! impl_hash_fn {

From 4fa9f1e1476b408b551064c9bb80fcb193c96073 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Thu, 20 May 2021 14:39:56 +0100
Subject: [PATCH 11/29] Inline debug_println!

---
 crates/env/src/lib.rs | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/crates/env/src/lib.rs b/crates/env/src/lib.rs
index 52e4b998da9..4a9d4a517e8 100644
--- a/crates/env/src/lib.rs
+++ b/crates/env/src/lib.rs
@@ -115,8 +115,7 @@ macro_rules! debug_print {
 #[macro_export]
 macro_rules! debug_println {
     () => ($crate::debug_print!("\n"));
-    ($($arg:tt)*) => ({
-        let msg = $crate::ink_prelude::format!($($arg)*);
-        $crate::debug_print!("{}\n", msg);
-    })
+    ($($arg:tt)*) => (
+        $crate::debug_print!("{}\n", $crate::ink_prelude::format!($($arg)*));
+    )
 }

From be0c00d8c1355f41047ef9a2851585bf4f8ea58b Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Thu, 20 May 2021 16:11:42 +0100
Subject: [PATCH 12/29] If logging is disabled then subsequent calls will be a
 no-op

---
 crates/engine/src/ext.rs                |  3 +++
 crates/env/src/backend.rs               |  4 ++--
 crates/env/src/engine/on_chain/ext.rs   | 29 ++++++++++++++++++++-----
 crates/env/src/engine/on_chain/impls.rs |  1 +
 crates/env/src/error.rs                 |  3 +++
 5 files changed, 32 insertions(+), 8 deletions(-)

diff --git a/crates/engine/src/ext.rs b/crates/engine/src/ext.rs
index de50e1d0dfa..6bb8b6a402e 100644
--- a/crates/engine/src/ext.rs
+++ b/crates/engine/src/ext.rs
@@ -91,6 +91,9 @@ define_error_codes! {
     CodeNotFound = 7,
     /// The account that was called is either no contract (e.g. user account) or is a tombstone.
     NotCallable = 8,
+    /// The call to `seal_debug_message` had no effect because debug message
+	/// recording was disabled.
+	LoggingDisabled = 9,
 }
 
 /// The raw return code returned by the host side.
diff --git a/crates/env/src/backend.rs b/crates/env/src/backend.rs
index 19f6a85d9e8..b79903ba0ea 100644
--- a/crates/env/src/backend.rs
+++ b/crates/env/src/backend.rs
@@ -121,8 +121,8 @@ pub trait EnvBackend {
     /// client. This buffer is also printed as a debug message to the node console if the
     /// `debug` log level is enabled for the `runtime::contracts` target.
     ///
-    /// This is a no-op if debug message recording is disabled which is always the case
-    /// when the code is executing on-chain.
+    /// If debug message recording is disabled in the contracts pallet, which is always the case
+    /// when the code is executing on-chain, then this will have no effect.
     fn debug_message(&mut self, content: &str);
 
     /// Conducts the crypto hash of the given input and stores the result in `output`.
diff --git a/crates/env/src/engine/on_chain/ext.rs b/crates/env/src/engine/on_chain/ext.rs
index 2d784930bc3..627d770966d 100644
--- a/crates/env/src/engine/on_chain/ext.rs
+++ b/crates/env/src/engine/on_chain/ext.rs
@@ -76,6 +76,9 @@ define_error_codes! {
     CodeNotFound = 7,
     /// The account that was called is either no contract (e.g. user account) or is a tombstone.
     NotCallable = 8,
+     /// The call to `seal_debug_message` had no effect because debug message
+	/// recording was disabled.
+	LoggingDisabled = 9,
 }
 
 /// Thin-wrapper around a `u32` representing a pointer for Wasm32.
@@ -604,12 +607,26 @@ pub fn random(subject: &[u8], output: &mut &mut [u8]) {
     extract_from_slice(output, output_len as usize);
 }
 
-pub fn debug_message(content: &str) {
-    let bytes = content.as_bytes();
-    // todo: handle return code
-    let _ret_code = unsafe {
-        sys::seal_debug_message(Ptr32::from_slice(bytes), bytes.len() as u32)
-    };
+/// If debug message recording is disabled in the contracts pallet, this will be set to false
+/// after an initial call in order to prevent the cost of further calls which will have no effect.
+static mut DEBUG_ENABLED: bool = true;
+
+/// Call `seal_debug_message` with the supplied UTF-8 encoded message.
+///
+/// If debug message recording is disabled in the contracts pallet, the first call to will return
+/// a LoggingDisabled error, and further calls will be a no-op to avoid the cost of calling into
+/// the supervisor.
+pub fn debug_message(message: &str) {
+    if unsafe { DEBUG_ENABLED } {
+        let bytes = message.as_bytes();
+        let ret_code = unsafe {
+            sys::seal_debug_message(Ptr32::from_slice(bytes), bytes.len() as u32)
+        };
+        match ret_code.into() {
+            Err(Error::LoggingDisabled) => unsafe { DEBUG_ENABLED = false },
+            _ => ()
+        }
+    }
 }
 
 macro_rules! impl_hash_fn {
diff --git a/crates/env/src/engine/on_chain/impls.rs b/crates/env/src/engine/on_chain/impls.rs
index ef951513721..29a11ee2610 100644
--- a/crates/env/src/engine/on_chain/impls.rs
+++ b/crates/env/src/engine/on_chain/impls.rs
@@ -106,6 +106,7 @@ impl From<ext::Error> for Error {
             ext::Error::NewContractNotFunded => Self::NewContractNotFunded,
             ext::Error::CodeNotFound => Self::CodeNotFound,
             ext::Error::NotCallable => Self::NotCallable,
+            ext::Error::LoggingDisabled => Self::LoggingDisabled,
         }
     }
 }
diff --git a/crates/env/src/error.rs b/crates/env/src/error.rs
index 32d4a145504..854f821b8d5 100644
--- a/crates/env/src/error.rs
+++ b/crates/env/src/error.rs
@@ -46,6 +46,9 @@ pub enum Error {
     NotCallable,
     /// An unknown error has occurred.
     UnknownError,
+    /// The call to `seal_debug_message` had no effect because debug message
+	/// recording was disabled.
+    LoggingDisabled,
 }
 
 /// A result of environmental operations.

From 62f6b106976149488f2ddd2fb87cb5f3ec036261 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Thu, 20 May 2021 16:49:52 +0100
Subject: [PATCH 13/29] Fmt

---
 crates/engine/src/ext.rs              | 4 ++--
 crates/env/src/engine/on_chain/ext.rs | 6 +++---
 crates/env/src/error.rs               | 2 +-
 3 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/crates/engine/src/ext.rs b/crates/engine/src/ext.rs
index 6bb8b6a402e..60bd8d06533 100644
--- a/crates/engine/src/ext.rs
+++ b/crates/engine/src/ext.rs
@@ -92,8 +92,8 @@ define_error_codes! {
     /// The account that was called is either no contract (e.g. user account) or is a tombstone.
     NotCallable = 8,
     /// The call to `seal_debug_message` had no effect because debug message
-	/// recording was disabled.
-	LoggingDisabled = 9,
+    /// recording was disabled.
+    LoggingDisabled = 9,
 }
 
 /// The raw return code returned by the host side.
diff --git a/crates/env/src/engine/on_chain/ext.rs b/crates/env/src/engine/on_chain/ext.rs
index 627d770966d..e7cc24ec5f6 100644
--- a/crates/env/src/engine/on_chain/ext.rs
+++ b/crates/env/src/engine/on_chain/ext.rs
@@ -77,8 +77,8 @@ define_error_codes! {
     /// The account that was called is either no contract (e.g. user account) or is a tombstone.
     NotCallable = 8,
      /// The call to `seal_debug_message` had no effect because debug message
-	/// recording was disabled.
-	LoggingDisabled = 9,
+    /// recording was disabled.
+    LoggingDisabled = 9,
 }
 
 /// Thin-wrapper around a `u32` representing a pointer for Wasm32.
@@ -624,7 +624,7 @@ pub fn debug_message(message: &str) {
         };
         match ret_code.into() {
             Err(Error::LoggingDisabled) => unsafe { DEBUG_ENABLED = false },
-            _ => ()
+            _ => (),
         }
     }
 }
diff --git a/crates/env/src/error.rs b/crates/env/src/error.rs
index 854f821b8d5..babd7c2e743 100644
--- a/crates/env/src/error.rs
+++ b/crates/env/src/error.rs
@@ -47,7 +47,7 @@ pub enum Error {
     /// An unknown error has occurred.
     UnknownError,
     /// The call to `seal_debug_message` had no effect because debug message
-	/// recording was disabled.
+    /// recording was disabled.
     LoggingDisabled,
 }
 

From 43aba01142d3abc403b81ed88de929b5562d3631 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Thu, 20 May 2021 16:57:32 +0100
Subject: [PATCH 14/29] Fix missing error match in experimental off-chain

---
 crates/env/src/engine/experimental_off_chain/impls.rs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/crates/env/src/engine/experimental_off_chain/impls.rs b/crates/env/src/engine/experimental_off_chain/impls.rs
index 1ce60f8bd8b..e3980e9bae0 100644
--- a/crates/env/src/engine/experimental_off_chain/impls.rs
+++ b/crates/env/src/engine/experimental_off_chain/impls.rs
@@ -109,6 +109,7 @@ impl From<ext::Error> for crate::Error {
             ext::Error::NewContractNotFunded => Self::NewContractNotFunded,
             ext::Error::CodeNotFound => Self::CodeNotFound,
             ext::Error::NotCallable => Self::NotCallable,
+            ext::Error::LoggingDisabled => Self::LoggingDisabled,
         }
     }
 }

From b978d76d0994a6ea43f48a334651425ffcf2bb44 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Thu, 20 May 2021 17:20:58 +0100
Subject: [PATCH 15/29] Add safety comment to debug_message

---
 crates/env/src/engine/on_chain/ext.rs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/crates/env/src/engine/on_chain/ext.rs b/crates/env/src/engine/on_chain/ext.rs
index e7cc24ec5f6..a5ce184bb3d 100644
--- a/crates/env/src/engine/on_chain/ext.rs
+++ b/crates/env/src/engine/on_chain/ext.rs
@@ -616,6 +616,11 @@ static mut DEBUG_ENABLED: bool = true;
 /// If debug message recording is disabled in the contracts pallet, the first call to will return
 /// a LoggingDisabled error, and further calls will be a no-op to avoid the cost of calling into
 /// the supervisor.
+///
+/// # Safety
+///
+/// Accesses to the static `DEBUG_ENABLED` are safe because we are executing in a single-threaded
+/// environment.
 pub fn debug_message(message: &str) {
     if unsafe { DEBUG_ENABLED } {
         let bytes = message.as_bytes();

From 35fcf72ad20205dc1d17ea21c4f4d6a26fd9e9c5 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Thu, 20 May 2021 17:33:22 +0100
Subject: [PATCH 16/29] Only re-export ink_prelude::format, and explain

---
 crates/env/src/lib.rs | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/crates/env/src/lib.rs b/crates/env/src/lib.rs
index 4a9d4a517e8..fb1d06a5797 100644
--- a/crates/env/src/lib.rs
+++ b/crates/env/src/lib.rs
@@ -99,7 +99,12 @@ pub use self::{
         NoChainExtension,
     },
 };
-pub use ink_prelude;
+
+/// Required by the `debug_print*` macros below, because there is no guarantee that contracts will
+/// have a direct `ink_prelude` dependency. In the future we could introduce an "umbrella" crate
+/// containing all the `ink!` crates which could also host these macros.
+#[doc(hidden)]
+pub use ink_prelude::format;
 
 /// Appends a formatted string to the `debug_message` buffer which will be:
 ///  - Returned to the caller when the contract is invoked via RPC (*not* via an extrinsic)
@@ -107,7 +112,7 @@ pub use ink_prelude;
 ///    console's `stdout` when the log level is set to `debug`.
 #[macro_export]
 macro_rules! debug_print {
-    ($($arg:tt)*) => ($crate::debug_message(&$crate::ink_prelude::format!($($arg)*)));
+    ($($arg:tt)*) => ($crate::debug_message(&$crate::format!($($arg)*)));
 }
 
 /// Appends a formatted string to the `debug_message` buffer, as per [`debug_print`] but
@@ -116,6 +121,6 @@ macro_rules! debug_print {
 macro_rules! debug_println {
     () => ($crate::debug_print!("\n"));
     ($($arg:tt)*) => (
-        $crate::debug_print!("{}\n", $crate::ink_prelude::format!($($arg)*));
+        $crate::debug_print!("{}\n", $crate::format!($($arg)*));
     )
 }

From d96dea07366bbccff9626d0fee5340b6bda90c5f Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Thu, 20 May 2021 17:35:10 +0100
Subject: [PATCH 17/29] Satisfy clippy

---
 crates/env/src/engine/on_chain/ext.rs | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/crates/env/src/engine/on_chain/ext.rs b/crates/env/src/engine/on_chain/ext.rs
index a5ce184bb3d..d71d255f148 100644
--- a/crates/env/src/engine/on_chain/ext.rs
+++ b/crates/env/src/engine/on_chain/ext.rs
@@ -627,9 +627,8 @@ pub fn debug_message(message: &str) {
         let ret_code = unsafe {
             sys::seal_debug_message(Ptr32::from_slice(bytes), bytes.len() as u32)
         };
-        match ret_code.into() {
-            Err(Error::LoggingDisabled) => unsafe { DEBUG_ENABLED = false },
-            _ => (),
+        if let Err(Error::LoggingDisabled) = ret_code.into() {
+            unsafe { DEBUG_ENABLED = false }
         }
     }
 }

From efa66bb4de544ac0dd1ebe72535844b63cfe1152 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Fri, 21 May 2021 10:52:51 +0100
Subject: [PATCH 18/29] Encapsulate DEBUG_ENABLED global in module

---
 crates/env/src/engine/on_chain/ext.rs | 52 ++++++++++++++++-----------
 1 file changed, 31 insertions(+), 21 deletions(-)

diff --git a/crates/env/src/engine/on_chain/ext.rs b/crates/env/src/engine/on_chain/ext.rs
index d71d255f148..a344b0e94ee 100644
--- a/crates/env/src/engine/on_chain/ext.rs
+++ b/crates/env/src/engine/on_chain/ext.rs
@@ -20,6 +20,8 @@ use crate::ReturnFlags;
 use core::marker::PhantomData;
 use ink_primitives::Key;
 
+pub use self::debug::debug_message;
+
 macro_rules! define_error_codes {
     (
         $(
@@ -607,28 +609,36 @@ pub fn random(subject: &[u8], output: &mut &mut [u8]) {
     extract_from_slice(output, output_len as usize);
 }
 
-/// If debug message recording is disabled in the contracts pallet, this will be set to false
-/// after an initial call in order to prevent the cost of further calls which will have no effect.
-static mut DEBUG_ENABLED: bool = true;
+mod debug {
+    use super::*;
 
-/// Call `seal_debug_message` with the supplied UTF-8 encoded message.
-///
-/// If debug message recording is disabled in the contracts pallet, the first call to will return
-/// a LoggingDisabled error, and further calls will be a no-op to avoid the cost of calling into
-/// the supervisor.
-///
-/// # Safety
-///
-/// Accesses to the static `DEBUG_ENABLED` are safe because we are executing in a single-threaded
-/// environment.
-pub fn debug_message(message: &str) {
-    if unsafe { DEBUG_ENABLED } {
-        let bytes = message.as_bytes();
-        let ret_code = unsafe {
-            sys::seal_debug_message(Ptr32::from_slice(bytes), bytes.len() as u32)
-        };
-        if let Err(Error::LoggingDisabled) = ret_code.into() {
-            unsafe { DEBUG_ENABLED = false }
+    /// If debug message recording is disabled in the contracts pallet, this will be set to false
+    /// after an initial call in order to prevent the cost of further calls which will have no effect.
+    static mut DEBUG_ENABLED: bool = true;
+
+    /// Call `seal_debug_message` with the supplied UTF-8 encoded message.
+    ///
+    /// If debug message recording is disabled in the contracts pallet, the first call to will return
+    /// a LoggingDisabled error, and further calls will be a no-op to avoid the cost of calling into
+    /// the supervisor.
+    ///
+    /// # Note
+    ///
+    /// This depends on the currently dsiabled
+    ///
+    /// # Safety
+    ///
+    /// Accesses to the static `DEBUG_ENABLED` are safe because we are executing in a single-threaded
+    /// environment.
+    pub fn debug_message(message: &str) {
+        if unsafe { DEBUG_ENABLED } {
+            let bytes = message.as_bytes();
+            let ret_code = unsafe {
+                sys::seal_debug_message(Ptr32::from_slice(bytes), bytes.len() as u32)
+            };
+            if let Err(Error::LoggingDisabled) = ret_code.into() {
+                unsafe { DEBUG_ENABLED = false }
+            }
         }
     }
 }

From 3c1b5a173b72f81609e3f9f195864b9706e71c0a Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Fri, 21 May 2021 11:16:52 +0100
Subject: [PATCH 19/29] Move seal_denug_message to unstable module

---
 crates/env/src/engine/on_chain/ext.rs | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/crates/env/src/engine/on_chain/ext.rs b/crates/env/src/engine/on_chain/ext.rs
index a344b0e94ee..51e9108f2f8 100644
--- a/crates/env/src/engine/on_chain/ext.rs
+++ b/crates/env/src/engine/on_chain/ext.rs
@@ -313,8 +313,6 @@ mod sys {
 
         pub fn seal_set_rent_allowance(value_ptr: Ptr32<[u8]>, value_len: u32);
 
-        pub fn seal_debug_message(str_ptr: Ptr32<[u8]>, str_len: u32) -> ReturnCode;
-
         pub fn seal_hash_keccak_256(
             input_ptr: Ptr32<[u8]>,
             input_len: u32,
@@ -346,6 +344,11 @@ mod sys {
             output_len_ptr: Ptr32Mut<u32>,
         );
     }
+
+    #[link(wasm_import_module = "__unstable__")]
+    extern "C" {
+        pub fn seal_debug_message(str_ptr: Ptr32<[u8]>, str_len: u32) -> ReturnCode;
+    }
 }
 
 fn extract_from_slice(output: &mut &mut [u8], new_len: usize) {

From 682ec0f647280333c30b951ffd04707272ffd81b Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Fri, 21 May 2021 11:39:46 +0100
Subject: [PATCH 20/29] Update unstable and safety comments

---
 crates/env/src/engine/on_chain/ext.rs | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/crates/env/src/engine/on_chain/ext.rs b/crates/env/src/engine/on_chain/ext.rs
index 51e9108f2f8..53ff202ca5f 100644
--- a/crates/env/src/engine/on_chain/ext.rs
+++ b/crates/env/src/engine/on_chain/ext.rs
@@ -621,25 +621,23 @@ mod debug {
 
     /// Call `seal_debug_message` with the supplied UTF-8 encoded message.
     ///
-    /// If debug message recording is disabled in the contracts pallet, the first call to will return
-    /// a LoggingDisabled error, and further calls will be a no-op to avoid the cost of calling into
-    /// the supervisor.
+    /// If debug message recording is disabled in the contracts pallet, the first call to will
+    /// return LoggingDisabled error, and further calls will be a no-op to avoid the cost of calling
+    /// into the supervisor.
     ///
     /// # Note
     ///
-    /// This depends on the currently dsiabled
-    ///
-    /// # Safety
-    ///
-    /// Accesses to the static `DEBUG_ENABLED` are safe because we are executing in a single-threaded
-    /// environment.
+    /// This depends on the the `seal_debug_message` interface which requires the
+    /// `"pallet-contracts/unstable-interface"` feature to be enabled in the target runtime.
     pub fn debug_message(message: &str) {
+        // SAFETY: safe because executing in a single threaded context
         if unsafe { DEBUG_ENABLED } {
             let bytes = message.as_bytes();
             let ret_code = unsafe {
                 sys::seal_debug_message(Ptr32::from_slice(bytes), bytes.len() as u32)
             };
             if let Err(Error::LoggingDisabled) = ret_code.into() {
+                // SAFETY: safe because executing in a single threaded context
                 unsafe { DEBUG_ENABLED = false }
             }
         }

From db05bd93b73d1ac2362299600521ff3bed95a9b5 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Mon, 24 May 2021 10:18:42 +0100
Subject: [PATCH 21/29] Add more comments about the required features to be
 enabled on the node runtime

---
 crates/env/src/lib.rs | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/crates/env/src/lib.rs b/crates/env/src/lib.rs
index fb1d06a5797..6182d8b1d12 100644
--- a/crates/env/src/lib.rs
+++ b/crates/env/src/lib.rs
@@ -110,6 +110,11 @@ pub use ink_prelude::format;
 ///  - Returned to the caller when the contract is invoked via RPC (*not* via an extrinsic)
 ///  - Logged as a `debug!` message on the substrate node, which will be printed to the node
 ///    console's `stdout` when the log level is set to `debug`.
+///
+/// # Note
+///
+/// This depends on the the `seal_debug_message` interface which requires the
+/// `"pallet-contracts/unstable-interface"` feature to be enabled in the target runtime.
 #[macro_export]
 macro_rules! debug_print {
     ($($arg:tt)*) => ($crate::debug_message(&$crate::format!($($arg)*)));
@@ -117,6 +122,11 @@ macro_rules! debug_print {
 
 /// Appends a formatted string to the `debug_message` buffer, as per [`debug_print`] but
 /// with a newline appended.
+///
+/// # Note
+///
+/// This depends on the the `seal_debug_message` interface which requires the
+/// `"pallet-contracts/unstable-interface"` feature to be enabled in the target runtime.
 #[macro_export]
 macro_rules! debug_println {
     () => ($crate::debug_print!("\n"));

From c6419504df67b1068b6549e309e8f6814474d18d Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Mon, 24 May 2021 11:14:12 +0100
Subject: [PATCH 22/29] Add `ink-debug` feature, make debug messages a noop if
 not enabled

---
 crates/env/Cargo.toml                 |  2 +
 crates/env/src/engine/on_chain/ext.rs |  9 +++
 crates/env/src/lib.rs                 | 83 +++++++++++++++++----------
 3 files changed, 63 insertions(+), 31 deletions(-)

diff --git a/crates/env/Cargo.toml b/crates/env/Cargo.toml
index bb712d4b48a..559a272107d 100644
--- a/crates/env/Cargo.toml
+++ b/crates/env/Cargo.toml
@@ -61,4 +61,6 @@ std = [
     "sha3",
     "blake2",
 ]
+# Enable contract debug messages via `debug_print!` and `debug_println!`.
+ink-debug = []
 ink-experimental-engine = ["ink_engine"]
diff --git a/crates/env/src/engine/on_chain/ext.rs b/crates/env/src/engine/on_chain/ext.rs
index 53ff202ca5f..9dcbe63e18b 100644
--- a/crates/env/src/engine/on_chain/ext.rs
+++ b/crates/env/src/engine/on_chain/ext.rs
@@ -345,6 +345,7 @@ mod sys {
         );
     }
 
+    #[cfg(feature = "ink-debug")]
     #[link(wasm_import_module = "__unstable__")]
     extern "C" {
         pub fn seal_debug_message(str_ptr: Ptr32<[u8]>, str_len: u32) -> ReturnCode;
@@ -612,6 +613,7 @@ pub fn random(subject: &[u8], output: &mut &mut [u8]) {
     extract_from_slice(output, output_len as usize);
 }
 
+#[cfg(feature = "ink-debug")]
 mod debug {
     use super::*;
 
@@ -644,6 +646,13 @@ mod debug {
     }
 }
 
+#[cfg(not(feature = "ink-debug"))]
+mod debug {
+    /// A no-op. Enable the `ink-debug` feature for debug messages.
+    pub fn debug_message(_message: &str) {
+    }
+}
+
 macro_rules! impl_hash_fn {
     ( $name:ident, $bytes_result:literal ) => {
         paste::item! {
diff --git a/crates/env/src/lib.rs b/crates/env/src/lib.rs
index 6182d8b1d12..5273384be33 100644
--- a/crates/env/src/lib.rs
+++ b/crates/env/src/lib.rs
@@ -100,37 +100,58 @@ pub use self::{
     },
 };
 
-/// Required by the `debug_print*` macros below, because there is no guarantee that contracts will
-/// have a direct `ink_prelude` dependency. In the future we could introduce an "umbrella" crate
-/// containing all the `ink!` crates which could also host these macros.
-#[doc(hidden)]
-pub use ink_prelude::format;
+cfg_if::cfg_if! {
+    if #[cfg(feature = "ink-debug")] {
+        /// Required by the `debug_print*` macros below, because there is no guarantee that contracts will
+        /// have a direct `ink_prelude` dependency. In the future we could introduce an "umbrella" crate
+        /// containing all the `ink!` crates which could also host these macros.
+        #[doc(hidden)]
+        pub use ink_prelude::format;
 
-/// Appends a formatted string to the `debug_message` buffer which will be:
-///  - Returned to the caller when the contract is invoked via RPC (*not* via an extrinsic)
-///  - Logged as a `debug!` message on the substrate node, which will be printed to the node
-///    console's `stdout` when the log level is set to `debug`.
-///
-/// # Note
-///
-/// This depends on the the `seal_debug_message` interface which requires the
-/// `"pallet-contracts/unstable-interface"` feature to be enabled in the target runtime.
-#[macro_export]
-macro_rules! debug_print {
-    ($($arg:tt)*) => ($crate::debug_message(&$crate::format!($($arg)*)));
-}
+        /// Appends a formatted string to the `debug_message` buffer which will be:
+        ///  - Returned to the caller when the contract is invoked via RPC (*not* via an extrinsic)
+        ///  - Logged as a `debug!` message on the substrate node, which will be printed to the node
+        ///    console's `stdout` when the log level is set to `debug`.
+        ///
+        /// # Note
+        ///
+        /// This depends on the the `seal_debug_message` interface which requires the
+        /// `"pallet-contracts/unstable-interface"` feature to be enabled in the target runtime.
+        #[cfg(feature = "ink-debug")]
+        #[macro_export]
+        macro_rules! debug_print {
+            ($($arg:tt)*) => ($crate::debug_message(&$crate::format!($($arg)*)));
+        }
 
-/// Appends a formatted string to the `debug_message` buffer, as per [`debug_print`] but
-/// with a newline appended.
-///
-/// # Note
-///
-/// This depends on the the `seal_debug_message` interface which requires the
-/// `"pallet-contracts/unstable-interface"` feature to be enabled in the target runtime.
-#[macro_export]
-macro_rules! debug_println {
-    () => ($crate::debug_print!("\n"));
-    ($($arg:tt)*) => (
-        $crate::debug_print!("{}\n", $crate::format!($($arg)*));
-    )
+        /// Appends a formatted string to the `debug_message` buffer, as per [`debug_print`] but
+        /// with a newline appended.
+        ///
+        /// # Note
+        ///
+        /// This depends on the the `seal_debug_message` interface which requires the
+        /// `"pallet-contracts/unstable-interface"` feature to be enabled in the target runtime.
+        #[cfg(feature = "ink-debug")]
+        #[macro_export]
+        macro_rules! debug_println {
+            () => ($crate::debug_print!("\n"));
+            ($($arg:tt)*) => (
+                $crate::debug_print!("{}\n", $crate::format!($($arg)*));
+            )
+        }
+    } else {
+        #[macro_export]
+        /// Debug messages disabled. Enable the `ink-debug` feature for contract debugging.
+        macro_rules! debug_print {
+            ($($arg:tt)*) => (debug_assert!(true));
+        }
+
+        #[macro_export]
+        /// Debug messages disabled. Enable the `ink-debug` feature for contract debugging.
+        macro_rules! debug_println {
+            () => (debug_assert!(true));
+            ($($arg:tt)*) => (
+                debug_assert!(true)
+            )
+        }
+    }
 }

From 89c3536adb3b599013415c932b57f117984c0ed2 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Mon, 24 May 2021 11:16:51 +0100
Subject: [PATCH 23/29] Fmt

---
 crates/env/src/engine/on_chain/ext.rs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/crates/env/src/engine/on_chain/ext.rs b/crates/env/src/engine/on_chain/ext.rs
index 9dcbe63e18b..91f5268199b 100644
--- a/crates/env/src/engine/on_chain/ext.rs
+++ b/crates/env/src/engine/on_chain/ext.rs
@@ -649,8 +649,7 @@ mod debug {
 #[cfg(not(feature = "ink-debug"))]
 mod debug {
     /// A no-op. Enable the `ink-debug` feature for debug messages.
-    pub fn debug_message(_message: &str) {
-    }
+    pub fn debug_message(_message: &str) {}
 }
 
 macro_rules! impl_hash_fn {

From 1fa7246c83f95881d8af0b127c72d33a7a36aff4 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Mon, 24 May 2021 11:20:07 +0100
Subject: [PATCH 24/29] Noop macro formatting

---
 crates/env/src/lib.rs | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/crates/env/src/lib.rs b/crates/env/src/lib.rs
index 5273384be33..2a06493e6f0 100644
--- a/crates/env/src/lib.rs
+++ b/crates/env/src/lib.rs
@@ -149,9 +149,7 @@ cfg_if::cfg_if! {
         /// Debug messages disabled. Enable the `ink-debug` feature for contract debugging.
         macro_rules! debug_println {
             () => (debug_assert!(true));
-            ($($arg:tt)*) => (
-                debug_assert!(true)
-            )
+            ($($arg:tt)*) => (debug_assert!(true))
         }
     }
 }

From dba097bd66efd0154354a4b204773d99da8268e5 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Mon, 24 May 2021 12:13:07 +0100
Subject: [PATCH 25/29] Enable debug printing for std

---
 crates/env/src/lib.rs | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/crates/env/src/lib.rs b/crates/env/src/lib.rs
index 2a06493e6f0..71d688a13d8 100644
--- a/crates/env/src/lib.rs
+++ b/crates/env/src/lib.rs
@@ -101,7 +101,7 @@ pub use self::{
 };
 
 cfg_if::cfg_if! {
-    if #[cfg(feature = "ink-debug")] {
+    if #[cfg(any(feature = "ink-debug", feature = "std"))] {
         /// Required by the `debug_print*` macros below, because there is no guarantee that contracts will
         /// have a direct `ink_prelude` dependency. In the future we could introduce an "umbrella" crate
         /// containing all the `ink!` crates which could also host these macros.
@@ -117,7 +117,6 @@ cfg_if::cfg_if! {
         ///
         /// This depends on the the `seal_debug_message` interface which requires the
         /// `"pallet-contracts/unstable-interface"` feature to be enabled in the target runtime.
-        #[cfg(feature = "ink-debug")]
         #[macro_export]
         macro_rules! debug_print {
             ($($arg:tt)*) => ($crate::debug_message(&$crate::format!($($arg)*)));
@@ -130,7 +129,6 @@ cfg_if::cfg_if! {
         ///
         /// This depends on the the `seal_debug_message` interface which requires the
         /// `"pallet-contracts/unstable-interface"` feature to be enabled in the target runtime.
-        #[cfg(feature = "ink-debug")]
         #[macro_export]
         macro_rules! debug_println {
             () => ($crate::debug_print!("\n"));

From 0de9b94dfc6be03bb26b0c1b639ef239e7887515 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Mon, 24 May 2021 12:14:40 +0100
Subject: [PATCH 26/29] Comment formatting

---
 crates/env/src/lib.rs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/crates/env/src/lib.rs b/crates/env/src/lib.rs
index 71d688a13d8..8ec831e0a86 100644
--- a/crates/env/src/lib.rs
+++ b/crates/env/src/lib.rs
@@ -102,9 +102,9 @@ pub use self::{
 
 cfg_if::cfg_if! {
     if #[cfg(any(feature = "ink-debug", feature = "std"))] {
-        /// Required by the `debug_print*` macros below, because there is no guarantee that contracts will
-        /// have a direct `ink_prelude` dependency. In the future we could introduce an "umbrella" crate
-        /// containing all the `ink!` crates which could also host these macros.
+        /// Required by the `debug_print*` macros below, because there is no guarantee that
+        /// contracts will have a direct `ink_prelude` dependency. In the future we could introduce
+        /// an "umbrella" crate containing all the `ink!` crates which could also host these macros.
         #[doc(hidden)]
         pub use ink_prelude::format;
 

From 57624062bee5c4904cd59a81e3096e78905fbf91 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Tue, 25 May 2021 09:36:05 +0100
Subject: [PATCH 27/29] Encapsulate static variable inside the function

---
 crates/env/src/engine/on_chain/ext.rs | 54 +++++++++++----------------
 1 file changed, 22 insertions(+), 32 deletions(-)

diff --git a/crates/env/src/engine/on_chain/ext.rs b/crates/env/src/engine/on_chain/ext.rs
index 91f5268199b..f11ae03a483 100644
--- a/crates/env/src/engine/on_chain/ext.rs
+++ b/crates/env/src/engine/on_chain/ext.rs
@@ -20,8 +20,6 @@ use crate::ReturnFlags;
 use core::marker::PhantomData;
 use ink_primitives::Key;
 
-pub use self::debug::debug_message;
-
 macro_rules! define_error_codes {
     (
         $(
@@ -614,43 +612,35 @@ pub fn random(subject: &[u8], output: &mut &mut [u8]) {
 }
 
 #[cfg(feature = "ink-debug")]
-mod debug {
-    use super::*;
-
-    /// If debug message recording is disabled in the contracts pallet, this will be set to false
-    /// after an initial call in order to prevent the cost of further calls which will have no effect.
+/// Call `seal_debug_message` with the supplied UTF-8 encoded message.
+///
+/// If debug message recording is disabled in the contracts pallet, the first call to will
+/// return LoggingDisabled error, and further calls will be a no-op to avoid the cost of calling
+/// into the supervisor.
+///
+/// # Note
+///
+/// This depends on the the `seal_debug_message` interface which requires the
+/// `"pallet-contracts/unstable-interface"` feature to be enabled in the target runtime.
+pub fn debug_message(message: &str) {
     static mut DEBUG_ENABLED: bool = true;
 
-    /// Call `seal_debug_message` with the supplied UTF-8 encoded message.
-    ///
-    /// If debug message recording is disabled in the contracts pallet, the first call to will
-    /// return LoggingDisabled error, and further calls will be a no-op to avoid the cost of calling
-    /// into the supervisor.
-    ///
-    /// # Note
-    ///
-    /// This depends on the the `seal_debug_message` interface which requires the
-    /// `"pallet-contracts/unstable-interface"` feature to be enabled in the target runtime.
-    pub fn debug_message(message: &str) {
-        // SAFETY: safe because executing in a single threaded context
-        if unsafe { DEBUG_ENABLED } {
-            let bytes = message.as_bytes();
-            let ret_code = unsafe {
-                sys::seal_debug_message(Ptr32::from_slice(bytes), bytes.len() as u32)
-            };
-            if let Err(Error::LoggingDisabled) = ret_code.into() {
-                // SAFETY: safe because executing in a single threaded context
-                unsafe { DEBUG_ENABLED = false }
-            }
+    // SAFETY: safe because executing in a single threaded context
+    if unsafe { DEBUG_ENABLED } {
+        let bytes = message.as_bytes();
+        let ret_code = unsafe {
+            sys::seal_debug_message(Ptr32::from_slice(bytes), bytes.len() as u32)
+        };
+        if let Err(Error::LoggingDisabled) = ret_code.into() {
+            // SAFETY: safe because executing in a single threaded context
+            unsafe { DEBUG_ENABLED = false }
         }
     }
 }
 
 #[cfg(not(feature = "ink-debug"))]
-mod debug {
-    /// A no-op. Enable the `ink-debug` feature for debug messages.
-    pub fn debug_message(_message: &str) {}
-}
+/// A no-op. Enable the `ink-debug` feature for debug messages.
+pub fn debug_message(_message: &str) {}
 
 macro_rules! impl_hash_fn {
     ( $name:ident, $bytes_result:literal ) => {

From 0524daa4018b2cab367d0ef91ec4fe092ebe5cc0 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Thu, 27 May 2021 15:23:46 +0100
Subject: [PATCH 28/29] Fmt

---
 crates/env/src/engine/on_chain/ext.rs | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/crates/env/src/engine/on_chain/ext.rs b/crates/env/src/engine/on_chain/ext.rs
index c243db0e6f6..d621247bef4 100644
--- a/crates/env/src/engine/on_chain/ext.rs
+++ b/crates/env/src/engine/on_chain/ext.rs
@@ -346,10 +346,7 @@ mod sys {
     #[link(wasm_import_module = "__unstable__")]
     extern "C" {
         #[cfg(feature = "ink-debug")]
-        pub fn seal_debug_message(
-            str_ptr: Ptr32<[u8]>,
-            str_len: u32
-        ) -> ReturnCode;
+        pub fn seal_debug_message(str_ptr: Ptr32<[u8]>, str_len: u32) -> ReturnCode;
 
         pub fn seal_rent_params(
             output_ptr: Ptr32Mut<[u8]>,

From 61d02809d67276489b88fbb789cbbe5d76a8fce5 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Thu, 27 May 2021 15:57:01 +0100
Subject: [PATCH 29/29] Remove debug_assert!(true) for disabled macros

---
 crates/env/src/lib.rs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/crates/env/src/lib.rs b/crates/env/src/lib.rs
index d4b0e7f1b67..ffe56c5dc56 100644
--- a/crates/env/src/lib.rs
+++ b/crates/env/src/lib.rs
@@ -143,14 +143,14 @@ cfg_if::cfg_if! {
         #[macro_export]
         /// Debug messages disabled. Enable the `ink-debug` feature for contract debugging.
         macro_rules! debug_print {
-            ($($arg:tt)*) => (debug_assert!(true));
+            ($($arg:tt)*) => ();
         }
 
         #[macro_export]
         /// Debug messages disabled. Enable the `ink-debug` feature for contract debugging.
         macro_rules! debug_println {
-            () => (debug_assert!(true));
-            ($($arg:tt)*) => (debug_assert!(true))
+            () => ();
+            ($($arg:tt)*) => ();
         }
     }
 }