Simple control flow analysis #1287
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| @@ -4,6 +4,7 @@ | |||
| /// <reference path="parser.ts"/> | |||
| /// <reference path="binder.ts"/> | |||
| /// <reference path="emitter.ts"/> | |||
| /// <reference path="controlflow.ts"/> | |||
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Consider controlFlow.ts, but I like this too.
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| return newLen - 1; | ||
| } | ||
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| function setFinalStateAtLabel(mergedStates: ControlFlowState, outerState: ControlFlowState, name: Identifier): void { |
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Leave a comment to explain that name is optional for the case of implicit labels.
| hasDefault = hasDefault || c.kind === SyntaxKind.DefaultClause; | ||
| setState(startState); | ||
| forEach(c.statements, check); | ||
| if (c.statements.length && currentState === ControlFlowState.Reachable) { |
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Consider c.statements.length > 0
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👍 Awesome job! |
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We should put this back on the radar again. |
👍 |
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IMO, it overlaps with TSLint. Regarding this, I'm concerned with the fact that I cannot use more mature JSHint or ESLint. Perhaps running them on the output (haven't tried that though). |
2 tasks
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closed in favor of #4788 |
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This PR adds a basic control flow analysis to typescript compiler. Now it can detect unreachable code, implicit returns of undefined in functions, unused labels, fall- through between cases in switch statements. Some of these checks can be used in #393 or #274.
Disclaimer: This PR is not intended to be checked in as-is. What I rather want is to use it as a starting point to discuss: