Re-review wc command#70
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Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
This reverts commit ec0373c.
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Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
This reverts commit 3c9cb2c.
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Review Summary
Reviewed the new wc builtin implementation across interp/builtins/wc/wc.go, registration, documentation updates, scenario tests, Go unit tests, GNU compat tests, and pentest tests.
Overall assessment: needs fixes
The implementation is well-structured with good security practices (sandbox-aware file access via callCtx.OpenFile, --files0-from intentionally blocked, context cancellation checks, streaming chunk-based reading). However, there are two bash compatibility bugs in the core counting logic that produce incorrect output.
Findings
| # | Priority | File | Finding |
|---|---|---|---|
| 1 |  |
interp/builtins/wc/wc.go:281 |
\v and \f incorrect lineLen handling in -L mode |
| 2 | |
interp/builtins/wc/wc.go:284-289 |
Control characters incorrectly start new words |
| 3 | |
interp/builtins/wc/wc_test.go:138-144 |
Tests assert wrong expected values for control char word count |
| 4 |  |
interp/builtins/wc/wc.go:261-263 |
Indentation inconsistency in countReader |
Test Coverage Summary
| Code path | Scenario test | Go test | Status |
|---|---|---|---|
| Default mode (lines, words, bytes) | default/basic.yaml + 3 more |
wc_test.go, wc_gnu_compat_test.go |
Covered |
-l lines counting |
lines/*.yaml (4 scenarios) |
wc_test.go:72-110 |
Covered |
-w word counting |
words/*.yaml (4 scenarios) |
wc_test.go:114-136 |
Covered |
-c byte counting |
bytes/*.yaml (2 scenarios) |
wc_test.go:148-170 |
Covered |
-m char counting |
chars/basic.yaml |
wc_test.go:174-204 |
Covered |
-L max line length |
max_line_length/*.yaml (5 scenarios) |
wc_test.go:208-238 |
Covered |
| Multiple files + total | multiple_files/total_line.yaml |
wc_test.go:242-259, wc_gnu_compat_test.go:130 |
Covered |
| Stdin implicit/explicit | stdin/*.yaml (2 scenarios) |
wc_test.go:263-284 |
Covered |
| Error: missing file | errors/missing_file.yaml |
wc_test.go:304-310 |
Covered |
| Error: unknown flag | errors/unknown_flag.yaml |
wc_test.go:312-317 |
Covered |
Error: --files0-from |
errors/files0_from_rejected.yaml |
builtin_wc_pentest_test.go:31-37 |
Covered |
| Sandbox escape | — | builtin_wc_pentest_test.go:44-52 |
Covered |
| Path traversal | — | builtin_wc_pentest_test.go:59-64 |
Covered |
| Chunk boundary (multibyte) | — | wc_test.go:441-453 |
Covered |
| Invalid UTF-8 at boundary | — | interp/builtin_wc_pentest_test.go:200-227 |
Covered |
\v / \f in -L mode |
— | — | Missing (and buggy) |
| Control char word counting | — | wc_test.go:138 (wrong expected) |
Buggy test |
| Symlinks (Unix) | — | wc_unix_test.go:19-35 |
Covered |
| Context cancellation | — | wc_test.go:343-350, pentest |
Covered |
| Large file / FD leak | — | pentest interp/builtin_wc_pentest_test.go:146-172 |
Covered |
Overall coverage: Gaps found — two code paths have incorrect behavior.
Positive Observations
- File access correctly goes through
callCtx.OpenFile(sandbox wrapper) — no directos.Open/os.Statcalls --files0-fromintentionally not implemented with a clear security comment referencing GTFOBins- Context cancellation is checked at every loop iteration in
countReader - Streaming chunk-based reading with 32 KiB buffer prevents memory exhaustion on large files
- UTF-8 carry buffer logic correctly handles multibyte characters spanning chunk boundaries
- Comprehensive pentest coverage including path traversal, sandbox escape, FD leak, large files, invalid UTF-8
skip_assert_against_bash: truecorrectly applied only to CJK/emoji display width scenarios (locale-dependent)
|
Iteration 1 self-review result: COMMENT (4 findings)
Proceeding to address findings. |
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… word counting, indentation - \f now resets lineLen (saves max first), matching GNU wc -L behavior - \v now has zero display width, matching GNU wc -L behavior - Control characters (unicode.Cc) no longer start new words, matching GNU wc -w - Fix indentation inconsistency in countReader carry handling - Update tests to expect correct GNU-compatible output (0 words for \x01) Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Review Summary (Iteration 2)
Reviewed the wc builtin implementation after fixes for the 3 P1 and 1 P3 findings from iteration 1.
Overall assessment: safe to merge
All previous findings have been addressed:
- P1 (fixed):
\vand\fnow handlelineLencorrectly in-Lmode -- verified against GNU wc. - P1 (fixed): Control characters no longer incorrectly start new words --
\x01\ncorrectly counts 0 words. - P1 (fixed): Test expected values now match correct bash behavior.
- P3 (fixed): Indentation inconsistency in
countReaderresolved.
Findings
No blocking issues found.
| # | Priority | File | Finding |
|---|---|---|---|
| 1 | |
tests/scenarios/cmd/wc/errors/files0_from_rejected.yaml |
Consider adding skip_assert_against_bash: true since this tests intentional divergence |
1. 
files0_from_rejected.yaml should mark intentional divergence
Severity: P3 (Code Quality)
Location: tests/scenarios/cmd/wc/errors/files0_from_rejected.yaml
Description: This scenario tests that --files0-from is rejected as an unknown flag (security restriction). GNU wc accepts this flag and instead fails because the file doesn't exist. Both happen to exit 1 with stderr containing wc:, so the bash comparison passes by coincidence. Per project conventions, scenarios testing intentional security divergence should have skip_assert_against_bash: true.
Remediation: Add skip_assert_against_bash: true to the scenario.
Test Coverage Summary
| Code path | Scenario test | Go test | Status |
|---|---|---|---|
| Default mode (lines, words, bytes) | default/*.yaml (4 scenarios) |
wc_test.go, wc_gnu_compat_test.go |
Covered |
-l lines counting |
lines/*.yaml (3 scenarios) |
wc_test.go |
Covered |
-w word counting |
words/*.yaml (4 scenarios) |
wc_test.go, wc_gnu_compat_test.go |
Covered |
-c byte counting |
bytes/*.yaml (2 scenarios) |
wc_test.go, wc_gnu_compat_test.go |
Covered |
-m char counting |
chars/basic.yaml |
wc_test.go |
Covered |
-L max line length |
max_line_length/*.yaml (5 scenarios) |
wc_test.go |
Covered |
| Multiple files + total | multiple_files/total_line.yaml |
wc_test.go, wc_gnu_compat_test.go |
Covered |
| Stdin implicit/explicit | stdin/*.yaml (2 scenarios) |
wc_test.go |
Covered |
| Error: missing file | errors/missing_file.yaml |
wc_test.go |
Covered |
| Error: unknown flag | errors/unknown_flag.yaml |
wc_test.go |
Covered |
Error: --files0-from |
errors/files0_from_rejected.yaml |
pentest | Covered |
| Sandbox escape | -- | builtin_wc_pentest_test.go |
Covered |
| Path traversal | -- | builtin_wc_pentest_test.go |
Covered |
| Chunk boundary (multibyte) | -- | wc_test.go:TestWcChunkBoundaryMultibyte |
Covered |
| Invalid UTF-8 at boundary | -- | interp/builtin_wc_pentest_test.go |
Covered |
| Control char word counting | -- | wc_test.go, wc_gnu_compat_test.go |
Covered |
Tab/CR in -L mode |
-- | wc_test.go |
Covered |
| Symlinks (Unix) | -- | wc_unix_test.go |
Covered |
| Context cancellation | -- | wc_test.go, pentest |
Covered |
| Large file / FD leak | -- | pentest | Covered |
Overall coverage: Adequate -- all code paths covered.
Positive Observations
- All file access correctly goes through
callCtx.OpenFilesandbox wrapper -- no directos.Open/os.Statcalls --files0-fromintentionally not implemented with clear GTFOBins security comment- Context cancellation checked at every loop iteration in
countReader - Streaming 32 KiB chunk-based reading prevents memory exhaustion
- Carry buffer logic for UTF-8 spanning chunk boundaries is correct and well-commented
- Control character handling now correctly matches GNU wc behavior (no word increment, no
inWordreset) \vcorrectly handled: zero display width, word-breaking, no lineLen modification\fcorrectly handled: lineLen reset with maxLineLen update, word-breaking- Tab width calculation
(lineLen/8 + 1) * 8matches GNU wc tab stop behavior - Comprehensive test pyramid: scenario tests (23), Go unit tests (40+), GNU compat tests (13), pentest tests (14), platform tests (2)
- Documentation updated in both
README.mdandSHELL_FEATURES.md
|
Iteration 2 self-review result: APPROVE (1 non-blocking P3 finding) All P1 issues from iteration 1 are confirmed fixed. One new P3 finding:
Proceeding to address the P3 finding. |
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This scenario tests intentional security divergence: rshell rejects --files0-from (GTFOBins risk) while GNU wc accepts it. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Review Summary (Iteration 3)
Reviewed the complete wc builtin implementation: interp/builtins/wc/wc.go (417 lines), registration in interp/register_builtins.go, pentest tests, unit tests, GNU compat tests, platform tests, 27 scenario tests, and documentation updates.
Overall assessment: Safe to merge. No P0, P1, or P2 findings.
All P1 issues from previous iterations have been fixed. The implementation is well-structured and secure.
Security
- File access goes through
callCtx.OpenFile(sandbox-safe). No directos.Open/os.Stat/os.ReadFilein the builtin. --files0-fromis intentionally blocked with a clear GTFOBins comment.- All imports are within the approved symbol allowlist. No unsafe/exec/net packages.
- Input is streamed in 32 KiB chunks; no unbounded memory allocation.
- Context cancellation is checked at each read loop iteration.
- File descriptors are closed via
defer rc.Close().
Bash Compatibility
- Verified key behaviors against
debian:bookworm-slimGNU wc: line counting, word counting (including control characters,\r,\v,\f), byte counting, max line length (tabs, CR reset, form feed). - All non-
skip_assert_against_bashscenario tests pass the bash comparison suite. -Ldisplay width uses Unicode width tables (intentionally diverges from locale-dependent bash behavior; CJK/emoji scenarios correctly markedskip_assert_against_bash: true).
Correctness
- Carry buffer for split UTF-8 at chunk boundaries is correctly implemented (verified by
TestWcChunkBoundaryMultibyteandTestWcPentestInvalidUTF8AtChunkBoundary). - Byte count accounting correctly subtracts carried bytes and re-adds them in the next iteration.
- Column width formatting matches GNU wc (minimum width 7 for stdin, right-justified to largest count).
- Error handling: partial failures still print counts for successful files + total line, exit code 1.
Test Coverage
| Code path | Scenario test | Go test | Status |
|---|---|---|---|
| Default mode (lines, words, bytes) | default/basic.yaml + 3 more |
TestWcDefaultBasic |
Covered |
-l line counting |
lines/*.yaml (4 scenarios) |
TestWcLines* (5 tests) |
Covered |
-w word counting |
words/*.yaml (4 scenarios) |
TestWcWords* (4 tests) |
Covered |
-c byte counting |
bytes/*.yaml (2 scenarios) |
TestWcBytes* (3 tests) |
Covered |
-m char counting (ASCII) |
chars/basic.yaml |
TestWcCharsASCII |
Covered |
-m char counting (multibyte) |
-- | TestWcCharsMultibyte, TestGNUCompatCharsMultibyte |
Covered (Go) |
-L max line length |
max_line_length/*.yaml (5) |
TestWcMaxLineLen* (4 tests) |
Covered |
| Multiple files + total | multiple_files/total_line.yaml |
TestWcMultipleFiles |
Covered |
| Stdin implicit/explicit | stdin/*.yaml (2 scenarios) |
TestWcStdinImplicit, TestWcStdinDash |
Covered |
| Error: missing file | errors/missing_file.yaml |
TestWcMissingFile |
Covered |
| Error: unknown flag | errors/unknown_flag.yaml |
TestWcUnknownFlag |
Covered |
Error: --files0-from blocked |
errors/files0_from_rejected.yaml |
TestWcGTFOBinsFiles0FromRejected |
Covered |
-- double-dash |
hardening/double_dash_separator.yaml |
TestWcDoubleDash |
Covered |
| Chunk boundary UTF-8 carry | -- | TestWcChunkBoundaryMultibyte |
Covered (Go) |
| Invalid UTF-8 at boundary | -- | TestWcPentestInvalidUTF8AtChunkBoundary |
Covered (Go) |
| Sandbox escape (traversal) | -- | TestWcGTFOBinsFileReadTraversal, TestWcGTFOBinsFileReadSandboxEscape |
Covered (Go) |
| Symlink follow / dangling | -- | TestWcSymlinkToFile, TestWcDanglingSymlink |
Covered (Go, unix) |
| Context cancellation | -- | TestWcPentestContextCancelled, TestWcContextCancellation |
Covered (Go) |
| Large file / long line | -- | TestWcPentestLargeFile, TestWcPentestLongLine |
Covered (Go) |
| FD leak (many files) | -- | TestWcPentestManyFiles |
Covered (Go) |
| Combined flags | -- | TestWcAllFlags, TestWcLinesAndWords, TestWcCharsAndBytes |
Covered (Go) |
Tab/CR in -L |
-- | TestWcMaxLineLenTab, TestWcMaxLineLenCR |
Covered (Go) |
| Binary/non-UTF8 input | -- | TestWcBinaryInput |
Covered (Go) |
| Pipe integration | ls/pipes/pipe_to_wc.yaml |
TestWcPipeInput |
Covered |
Coverage status: Adequate. All code paths are covered by either scenario tests or Go tests.
Positive Observations
- Excellent pentest coverage across two test files (interp-level and package-level), including GTFOBins-specific vectors.
- The carry-buffer design for handling split multibyte characters at chunk boundaries is well-commented and correct.
- Memory safety is enforced by design: fixed 32 KiB buffer, streaming I/O, no file-size-dependent allocation.
- The
--files0-fromexclusion is proactive security hardening with a clear GTFOBins reference. - Good use of
skip_assert_against_bash: trueonly where behavior intentionally diverges (CJK/emoji display width). - Documentation (
README.md,SHELL_FEATURES.md) updated appropriately.
No findings to report. Clean implementation ready for merge.
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Iteration 3 self-review result: APPROVE (0 findings) All previous issues confirmed fixed. Implementation is clean, secure, and well-tested. No new findings. |
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Review Summary
Reviewed the new wc builtin command implementation: core counting logic (wc.go), registration, scenario tests, Go unit tests, GNU compat tests, pentest tests, and documentation updates.
Overall Assessment: needs fixes
The implementation is well-structured and follows established patterns. Security is solid: file access goes through callCtx.OpenFile, --files0-from is correctly blocked, sandbox escape tests are thorough, context cancellation is checked on every read iteration, and input is streamed in fixed-size chunks. The UTF-8 carry buffer logic for chunk boundaries is correctly implemented.
However, one scenario test has a wrong expected value and currently fails when run.
Findings
| # | Priority | File | Finding |
|---|---|---|---|
| 1 | |
tests/scenarios/cmd/ls/pipes/pipe_to_wc.yaml:17-18 |
Scenario test expects padded output but wc -l from stdin produces unpadded — test fails |
| 2 | |
tests/scenarios/cmd/wc/errors/missing_file.yaml:9 |
Prefer stderr (exact match) over stderr_contains per project conventions |
Coverage Summary
| Code path | Scenario test | Go test | Status |
|---|---|---|---|
| Default mode (lines, words, bytes) | default/basic.yaml + 3 others |
TestWcDefaultBasic |
Covered |
-l lines counting |
lines/*.yaml (4 scenarios) |
TestWcLines* (4 tests) |
Covered |
-w word counting |
words/*.yaml (4 scenarios) |
TestWcWords* (4 tests) |
Covered |
-c byte counting |
bytes/*.yaml (2 scenarios) |
TestWcBytes* (3 tests) |
Covered |
-m char counting |
chars/basic.yaml |
TestWcChars* (3 tests) |
Covered |
-L max line length |
max_line_length/*.yaml (5 scenarios) |
TestWcMaxLineLen* (4 tests) |
Covered |
-c -m combined |
— | TestWcCharsAndBytes |
Covered (Go only) |
| Multiple files + total | multiple_files/total_line.yaml |
TestWcMultipleFiles |
Covered |
| Stdin implicit/explicit | stdin/*.yaml (2 scenarios) |
TestWcStdin* (3 tests) |
Covered |
| Error: missing file | errors/missing_file.yaml |
TestWcMissingFile |
Covered |
| Error: unknown flag | errors/unknown_flag.yaml |
TestWcUnknownFlag |
Covered |
--files0-from blocked |
errors/files0_from_rejected.yaml |
TestWcFiles0FromRejected |
Covered |
-- flag separator |
hardening/double_dash_separator.yaml |
TestWcDoubleDash |
Covered |
CJK/emoji display width (-L) |
2 scenarios (skip_assert_against_bash) | TestWcChunkBoundaryMultibyte |
Covered |
| CR/CRLF handling | — | TestWcMaxLineLenCR*, TestWcCRLFLineCount |
Covered (Go only) |
Tab stop calculation (-L) |
— | TestWcMaxLineLenTab |
Covered (Go only) |
| UTF-8 chunk boundary carry | — | TestWcChunkBoundaryMultibyte, pentest |
Covered (Go only) |
| Sandbox escape (path traversal) | — | TestWcGTFOBinsFileReadTraversal |
Covered (Go only) |
| Sandbox escape (out of allowed paths) | — | TestWcGTFOBinsFileReadSandboxEscape |
Covered (Go only) |
| Context cancellation/timeout | — | TestWcContextCancellation, pentest |
Covered (Go only) |
| Large file / FD leak / long lines | — | pentest tests (5 tests) | Covered (Go only) |
| Symlinks (unix) | — | TestWcSymlinkToFile, TestWcDanglingSymlink |
Covered (Go only) |
| Binary/invalid UTF-8 input | — | TestWcBinaryInput, pentest |
Covered (Go only) |
Overall coverage: Adequate — all core code paths are covered.
Positive Observations
- File access correctly uses
callCtx.OpenFile— no directos.Open/os.Statcalls --files0-fromdeliberately omitted with clear GTFOBins security comment- Context cancellation checked on every read loop iteration
- Fixed 32 KiB chunk streaming prevents unbounded memory usage
- Carry buffer for UTF-8 across chunk boundaries is well-implemented
- Comprehensive pentest suite covering FD leaks, large inputs, invalid UTF-8, path traversal
- Good separation: scenario tests for bash compatibility, Go tests for edge cases and security
- Tab stop calculation, CR reset, form feed reset all match GNU wc behavior
- Control characters correctly handled in word counting (transparent, not word-starting)
stdinMinWidthpadding logic correctly conditioned onnCols >= 2
| wc bogusfile | ||
| expect: | ||
| stdout: "" | ||
| stderr_contains: ["wc: bogusfile:"] |
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stderr exact match over stderr_contains
Per project conventions in AGENTS.md: "use expect.stderr when possible instead of stderr_contains." Since the error message format is deterministic (wc: bogusfile: No such file or directory\n), an exact match would be more precise. Note that this scenario is asserted against bash by default, so the exact string can be validated.
| stderr_contains: ["wc: bogusfile:"] | |
| stderr: "wc: bogusfile: No such file or directory\n" |
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[Claude Opus 4.6] Investigated — the exact stderr from rshell is wc: bogusfile: openat bogusfile: no such file or directory\n which differs from bash's wc: bogusfile: No such file or directory\n. Using exact stderr would require skip_assert_against_bash: true. Keeping stderr_contains as the appropriate assertion since the error format differs cross-platform. The underlying error message format is a broader issue beyond this PR scope.
|
Iteration 1 self-review result: COMMENT
Review posted at: #70 (review) |
…output The scenario expected padded output (stdinMinWidth=7) but wc -l from stdin with a single output column correctly produces unpadded "3\n", matching bash behavior. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Review Summary (Iteration 2)
Reviewed the wc builtin implementation including:
interp/builtins/wc/wc.go— core implementationinterp/builtins/wc/wc_test.go,wc_gnu_compat_test.go,wc_unix_test.go— Go testsinterp/builtin_wc_pentest_test.go— security/pentest testsinterp/register_builtins.go— registration- 27 YAML scenario tests in
tests/scenarios/cmd/wc/ tests/scenarios/cmd/ls/pipes/pipe_to_wc.yaml- Documentation updates in
README.mdandSHELL_FEATURES.md
Overall Assessment: APPROVE — Safe to merge
The iteration 1 fixes are correct. All tests pass, including bash comparison tests (RSHELL_BASH_TEST=1). The implementation is solid:
Security: File access goes through callCtx.OpenFile() (sandbox-aware). No direct os.Open/os.Stat calls. --files0-from is intentionally blocked (GTFOBins risk). Context cancellation is checked each read loop iteration. Fixed-size 32 KiB read buffer prevents unbounded memory allocation. No unsafe, os/exec, or net/http imports.
Bash Compatibility: Verified against GNU wc on debian:bookworm-slim. Key behaviors match: \r/\v/\f word breaking, \r/\f line-length reset, \v zero display width, \t tab-stop calculation, control character word semantics, stdin min-width padding (7-char only with 2+ columns), and field width formatting.
Correctness: The P1 fix from iteration 1 (stdin min-width padding with single column) is correctly implemented with nCols >= 2 check. The \r maxLineLen save-before-reset fix is correct. UTF-8 chunk boundary handling with carry buffer is sound.
Findings
No P0, P1, or P2 findings.
| # | Priority | File | Finding |
|---|---|---|---|
| 1 | |
tests/scenarios/cmd/wc/chars/ |
No multibyte character scenario test |
| 2 | |
interp/builtins/wc/wc.go:287 |
Variable r (rune) shadows parameter r (io.Reader) |
P3 Details
1. No multibyte character scenario test for -m
The tests/scenarios/cmd/wc/chars/basic.yaml only tests ASCII (hello\n). Multibyte character counting (e.g. café\n → 5 chars vs 6 bytes) is only tested in Go tests (TestWcCharsMultibyte, TestWcCharsAndBytes). A scenario test would provide bash-comparison validation, though note that -m behavior is locale-dependent in GNU wc (rshell always uses UTF-8, which is the right choice for an AI agent shell).
2. Variable shadowing
r is used both as the io.Reader parameter and as a rune in the inner loop. This compiles correctly and the reader is not referenced inside the loop, but it could confuse future maintainers.
Positive Observations
- Comprehensive test coverage: 27 scenario tests, GNU compat tests, pentest tests, platform-specific tests, and chunk-boundary edge case tests
- Proper sandbox integration via
callCtx.OpenFile() - Streaming design (32 KiB chunks) with no unbounded memory allocation
- Context cancellation checked at each read iteration
--files0-fromintentionally blocked with clear security comment- Good handling of partial failures (error on one file doesn't skip others)
- Correct
skip_assert_against_bashusage for intentional divergences (CJK/emoji display width,--files0-fromrejection)
| expect: | ||
| stdout: "6 file.txt\n" | ||
| stderr: "" | ||
| exit_code: 0 |
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-m
This only tests ASCII. Multibyte counting (e.g. café\n → 5 chars, 6 bytes) is covered by Go tests but not by a scenario test. A scenario test would provide automatic bash-comparison validation.
Note: since -m is locale-dependent in GNU wc, any multibyte scenario would need skip_assert_against_bash: true (the Docker container uses C locale where -m equals -c).
Nice-to-have: add a chars/multibyte.yaml with skip_assert_against_bash: true.
| c.bytes -= int64(carryN) | ||
|
|
||
| for i := 0; i < len(chunk); { | ||
| r, size := utf8.DecodeRune(chunk[i:]) |
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r (rune) shadows r (io.Reader)
The loop variable r shadows the function parameter r io.Reader. This compiles fine and works correctly since the reader isn't referenced inside the loop, but it could confuse future readers of this code.
| r, size := utf8.DecodeRune(chunk[i:]) | |
| ru, size := utf8.DecodeRune(chunk[i:]) |
(Would require renaming all r references to ru in the loop body.)
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Iteration 2 self-review result: APPROVE
All unit tests, pentest tests, scenario tests, and bash comparison tests pass. The iteration 1 fix (pipe_to_wc.yaml expected stdout) is correctly implemented. |
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Reviewed commit: bca4408307
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Iteration 3 self-review result: APPROVE
All tests pass. @codex repeat findings (non-ASCII whitespace, malformed UTF-8, wide emoji) addressed as invalid — all are locale-dependent behaviors where rshell intentionally diverges from C-locale GNU wc. Threads resolved. |
Summary
Testing
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Review-Fix Loop Summary
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Summary
Testing
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Reviewed commit: 4fc9e083a9
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| width := fieldWidth(total, opts) | ||
| if hasStdin && width < stdinMinWidth { | ||
| nCols := opts.columnCount() | ||
| if hasStdin && nCols >= 2 && width < stdinMinWidth { |
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The new hasStdin && nCols >= 2 guard drops GNU-compatible padding for cases that still require the 7-character stdin field width when only one count column is selected but multiple inputs are printed. For example, with GNU wc, printf 'a\n' | wc -l - file produces padded counts (" 1 -", " 1 file", " 2 total"), but this branch leaves width at 1 and emits unpadded output. This is a user-visible formatting regression for mixed stdin+file invocations in single-column mode.
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Summary
Implement the
wc(word count) builtin command for the restricted shell interpreter.Features
-l(lines),-w(words),-c(bytes),-m(chars),-L(max line length) flags-)-Ldisplay widthBash compatibility fixes (iterative review)
\vhas zero display width,\fsaves max then resets line position (matching GNU wc)\rsaves maxLineLen before resetting (fixes undercounting when pre-CR segment is longer)pipe_to_wc.yamlexpected stdout fixed to unpadded3\nfor single-columnwc -lSecurity
--files0-fromintentionally blocked (GTFOBins data exfiltration vector)callCtx.OpenFile(sandbox-safe)Other changes
files0_from_rejected.yamlmarked withskip_assert_against_bash: true(intentional divergence)AGENTS.mdand CI workflow updatesprintf,strings, andtailbuiltinsTest plan
wc_test.go) — all passwc_gnu_compat_test.go) — all passRSHELL_BASH_TEST=1) — all pass🤖 Generated with Claude Code