From 33c73dba2e08c92aafe7c7c6169a34358b70e192 Mon Sep 17 00:00:00 2001
From: Andy Hanson <anhans@microsoft.com>
Date: Tue, 20 Mar 2018 15:24:37 -0700
Subject: [PATCH] organizeImports: Preserve comments of deleted
 ImportDeclarations

---
 src/harness/unittests/organizeImports.ts      |  1 +
 src/services/organizeImports.ts               | 19 ++++++++++++++-----
 .../reference/organizeImports/Unused_Some.ts  |  2 ++
 3 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/src/harness/unittests/organizeImports.ts b/src/harness/unittests/organizeImports.ts
index de4a4722d67dc..73ead441562ef 100644
--- a/src/harness/unittests/organizeImports.ts
+++ b/src/harness/unittests/organizeImports.ts
@@ -217,6 +217,7 @@ F2();
                 {
                     path: "/test.ts",
                     content: `
+/** Comment */
 import { F1, F2 } from "lib";
 import * as NS from "lib";
 import D from "lib";
diff --git a/src/services/organizeImports.ts b/src/services/organizeImports.ts
index f6489fce6d208..81f8049bc50e9 100644
--- a/src/services/organizeImports.ts
+++ b/src/services/organizeImports.ts
@@ -34,21 +34,23 @@ namespace ts.OrganizeImports {
                 return;
             }
 
+            const deletedImportDeclarations = createMap<true>();
+
             const oldImportGroups = group(oldImportDecls, importDecl => getExternalModuleName(importDecl.moduleSpecifier));
             const sortedImportGroups = stableSort(oldImportGroups, (group1, group2) => compareModuleSpecifiers(group1[0].moduleSpecifier, group2[0].moduleSpecifier));
             const newImportDecls = flatMap(sortedImportGroups, importGroup =>
                 getExternalModuleName(importGroup[0].moduleSpecifier)
-                    ? coalesceImports(removeUnusedImports(importGroup, sourceFile, program))
+                    ? coalesceImports(removeUnusedImports(importGroup, sourceFile, program, deletedImportDeclarations))
                     : importGroup);
 
             // Delete or replace the first import.
             if (newImportDecls.length === 0) {
-                changeTracker.deleteNode(sourceFile, oldImportDecls[0]);
+                removeOldImport(newImportDecls[0]);
             }
             else {
                 // Note: Delete the surrounding trivia because it will have been retained in newImportDecls.
                 changeTracker.replaceNodeWithNodes(sourceFile, oldImportDecls[0], newImportDecls, {
-                    useNonAdjustedStartPosition: false,
+                    useNonAdjustedStartPosition: deletedImportDeclarations.has(String(getNodeId(oldImportDecls[0]))),
                     useNonAdjustedEndPosition: false,
                     suffix: getNewLineOrDefaultFromHost(host, formatContext.options),
                 });
@@ -56,7 +58,11 @@ namespace ts.OrganizeImports {
 
             // Delete any subsequent imports.
             for (let i = 1; i < oldImportDecls.length; i++) {
-                changeTracker.deleteNode(sourceFile, oldImportDecls[i]);
+                removeOldImport(oldImportDecls[i]);
+            }
+
+            function removeOldImport(oldImport: ImportDeclaration): void {
+                changeTracker.deleteNode(sourceFile, oldImport, { useNonAdjustedStartPosition: deletedImportDeclarations.has(String(getNodeId(oldImport))) });
             }
         }
     }
@@ -66,7 +72,7 @@ namespace ts.OrganizeImports {
         return body && !isIdentifier(body) && (isModuleBlock(body) ? body : getModuleBlock(body));
     }
 
-    function removeUnusedImports(oldImports: ReadonlyArray<ImportDeclaration>, sourceFile: SourceFile, program: Program) {
+    function removeUnusedImports(oldImports: ReadonlyArray<ImportDeclaration>, sourceFile: SourceFile, program: Program, deletedImportDeclarations: Map<true>) {
         const typeChecker = program.getTypeChecker();
         const jsxNamespace = typeChecker.getJsxNamespace();
         const jsxContext = sourceFile.languageVariant === LanguageVariant.JSX && program.getCompilerOptions().jsx;
@@ -110,6 +116,9 @@ namespace ts.OrganizeImports {
             if (name || namedBindings) {
                 usedImports.push(updateImportDeclarationAndClause(importDecl, name, namedBindings));
             }
+            else {
+                deletedImportDeclarations.set(String(getNodeId(importDecl)), true);
+            }
         }
 
         return usedImports;
diff --git a/tests/baselines/reference/organizeImports/Unused_Some.ts b/tests/baselines/reference/organizeImports/Unused_Some.ts
index 2f0aaa6d49991..9347d722add2d 100644
--- a/tests/baselines/reference/organizeImports/Unused_Some.ts
+++ b/tests/baselines/reference/organizeImports/Unused_Some.ts
@@ -1,5 +1,6 @@
 // ==ORIGINAL==
 
+/** Comment */
 import { F1, F2 } from "lib";
 import * as NS from "lib";
 import D from "lib";
@@ -8,6 +9,7 @@ D();
 
 // ==ORGANIZED==
 
+/** Comment */
 import D from "lib";
 
 D();