Warning 20 range: also walk through let/use bindings (follow-up to #19504)#19896
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- Walk through let/use bindings in addition to Sequential when locating
the offending expression for warning 20. Fixes the case Eugene flagged:
for _ in [] do
let x = 1
x
- Fix wrong issue link (#5735 -> #5418) in code comment, release notes,
and test annotations.
- Add regression tests for the let/use case (single + nested bindings).
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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… add PR link - Remove issue URL references from code comments and test methods (per auduchinok: redundant, commit links to PR with full context) - Add test for 'use' binding (non-unit after use) - Add test for computation expression after let binding - Add PR #19896 link to release notes Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
…0-let-binding-range
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
…dy covers the user-facing fix Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
The previous 'computation expression after let binding' test only used
async { return x } as a non-unit value - it didn't exercise CE-specific
syntax constructs. Replace with a while-loop test that genuinely exercises
the TcStmt lastExprRange fix in a different loop context.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Follow-up to #19504 addressing review feedback from @auduchinok.
#19504 fixed warning 20 ("expression is implicitly ignored") to point at the last expression of a sequential body inside
for/while. The walk only descended throughSynExpr.Sequential, so when the last expression was the body of alet/usebinding, the squiggle covered the wholeletexpression instead of just the offending tail:This PR also descends through
SynExpr.LetOrUse, so the squiggle lands onxalone in cases like the one above.It also corrects the issue reference cited by the original PR (#5418 — "Wrong expression is ignored warning range"; the previously cited #5735 is unrelated to this diagnostic).
Tracking: #5418