repl: add function signature hints#64610
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@hemanth every time a PR is opened and closed it pings maintainers. May I suggest verifying the branch is correct before opening a PR? |
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When typing a function name followed by '(', the REPL now displays
a dimmed hint below the input line showing the function's parameters.
For example, typing 'console.log(' shows:
// console.log(...data)
Uses the inspector to safely extract parameter lists via
Function.prototype.toString(), with throwOnSideEffect to prevent
unintended evaluation.
PR-URL: nodejs#64610
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When typing a function name followed by '(', the REPL now displays
a dimmed hint below the input line showing the function's parameters.
For example, typing 'console.log(' shows:
// console.log(...data)
Uses the inspector to safely extract parameter lists via
Function.prototype.toString(), with throwOnSideEffect to prevent
unintended evaluation.
PR-URL: nodejs#64610
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Multiple PRs, multiple branches! After splitting the larger PR it has caused few side-effects, cleaned up the branch, please review @avivkeller thank you! |
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When typing a function name followed by '(', the REPL now displays
a dimmed hint below the input line showing the function's parameters.
For example, typing 'console.log(' shows:
// console.log(...data)
Uses the inspector to safely extract parameter lists via
Function.prototype.toString(), with throwOnSideEffect to prevent
unintended evaluation.
PR-URL: nodejs#64610
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When typing a function name followed by '(', the REPL now displays
a dimmed hint below the input line showing the function's parameters.
For example, typing 'console.log(' shows:
// console.log(...data)
Uses the inspector to safely extract parameter lists via
Function.prototype.toString(), with throwOnSideEffect to prevent
unintended evaluation.
PR-URL: nodejs#64610
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Comment on lines
+926
to
+957
| // Find the function name before the opening parenthesis. | ||
| // Look backwards from cursor for pattern: identifier( | ||
| let parenPos = -1; | ||
| for (let i = cursor - 1; i >= 0; i--) { | ||
| const ch = StringPrototypeCharCodeAt(line, i); | ||
| if (ch === 40) { // '(' | ||
| parenPos = i; | ||
| break; | ||
| } | ||
| // If we hit anything other than whitespace or content after '(', | ||
| // stop looking. | ||
| if (ch !== 32 && ch !== 9) break; // space, tab | ||
| } | ||
|
|
||
| if (parenPos < 0) return; | ||
|
|
||
| // Extract the expression before the '(' - supports simple names | ||
| // (e.g. `foo(`) and dotted access (e.g. `console.log(`). | ||
| // Parenthesized expressions like `(fn)(` are not handled; | ||
| // the hint is silently skipped in that case. | ||
| const nameEnd = parenPos; | ||
| let nameStart = nameEnd; | ||
| for (let i = nameEnd - 1; i >= 0; i--) { | ||
| const ch = StringPrototypeCharCodeAt(line, i); | ||
| // Allow identifier chars and dots for property access. | ||
| if ((ch >= 65 && ch <= 90) || (ch >= 97 && ch <= 122) || | ||
| (ch >= 48 && ch <= 57) || ch === 95 || ch === 36 || ch === 46) { | ||
| nameStart = i; | ||
| } else { | ||
| break; | ||
| } | ||
| } |
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How do we get the expression for auto completion? Can we reuse that logic here?
| throwOnSideEffect: true, | ||
| timeout: 200, | ||
| contextId: repl[contextSymbol], | ||
| }).then((preview) => { |
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Would it be cleaner to make this function asynchronous?
Comment on lines
+680
to
+691
| let showSignatureHint; | ||
| let clearSignatureHint; | ||
| if (preview && this.terminal && process.features.inspector && | ||
| process.env.TERM !== 'dumb') { | ||
| ({ showSignatureHint, clearSignatureHint } = setupSignatureHint( | ||
| this, | ||
| kContextId, | ||
| )); | ||
| } else { | ||
| showSignatureHint = () => {}; | ||
| clearSignatureHint = () => {}; | ||
| } |
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Rather than setting functions to no-ops, we can use ?.()
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I know I'm leaving a lot of reviews, and I'm very sorry, keep in mind, these are just reviews, and you're not obligated to accept them
Codecov Report❌ Patch coverage is
Additional details and impacted files@@ Coverage Diff @@
## main #64610 +/- ##
==========================================
- Coverage 90.14% 90.13% -0.01%
==========================================
Files 741 741
Lines 242080 242248 +168
Branches 45563 45593 +30
==========================================
+ Hits 218213 218343 +130
- Misses 15375 15404 +29
- Partials 8492 8501 +9
🚀 New features to boost your workflow:
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When typing a function name followed by '(', the REPL now displays
a dimmed hint below the input line showing the function's parameters.
For example, typing 'console.log(' shows:
// console.log(...data)
Uses the inspector to safely extract parameter lists via
Function.prototype.toString(), with throwOnSideEffect to prevent
unintended evaluation.
PR-URL: nodejs#64610
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Split from #64443 per review feedback to use idiomatic single-feature PRs.
When the user types
functionName(, the REPL displays the function's parameter list as a dimmed hint below the input line. Uses the V8 Inspector protocol withthrowOnSideEffect: truefor safety.Requires
previewto be enabled and the inspector to be available.Refs: #48164