Deoptimize all parameters when losing track of a function (#5158)

lukastaegert · web-flow · commit 4e92d60fa90c · 2023-09-28T06:51:13.000+02:00
diff --git a/src/ast/nodes/shared/FunctionBase.ts b/src/ast/nodes/shared/FunctionBase.ts
@@ -74,8 +74,13 @@ export default abstract class FunctionBase extends NodeBase {
 		this.getObjectEntity().deoptimizePath(path);
 		if (path.length === 1 && path[0] === UnknownKey) {
 			// A reassignment of UNKNOWN_PATH is considered equivalent to having lost track
-			// which means the return expression needs to be reassigned
+			// which means the return expression and parameters need to be reassigned
 			this.scope.getReturnExpression().deoptimizePath(UNKNOWN_PATH);
+			for (const parameterList of this.scope.parameters) {
+				for (const parameter of parameterList) {
+					parameter.deoptimizePath(UNKNOWN_PATH);
+				}
+			}
 		}
 	}
 
diff --git a/test/function/samples/mutate-via-parameter/_config.js b/test/function/samples/mutate-via-parameter/_config.js
@@ -0,0 +1,9 @@
+const assert = require('node:assert');
+
+module.exports = defineTest({
+	description:
+		'respects variable mutations via unknown parameter values if we lose track of a function',
+	exports({ test }) {
+		assert.ok(test(state => (state.modified = true)));
+	}
+});
diff --git a/test/function/samples/mutate-via-parameter/main.js b/test/function/samples/mutate-via-parameter/main.js
@@ -0,0 +1,8 @@
+export function test(callback) {
+	const state = {
+		modified: false
+	};
+	callback(state);
+	if (state.modified) return true;
+	return false;
+}

Original file line number	Diff line number	Diff line change
`@@ -74,8 +74,13 @@ export default abstract class FunctionBase extends NodeBase {`
`74`	`74`	`this.getObjectEntity().deoptimizePath(path);`
`75`	`75`	`if (path.length === 1 && path[0] === UnknownKey) {`
`76`	`76`	`// A reassignment of UNKNOWN_PATH is considered equivalent to having lost track`
`77`		`- // which means the return expression needs to be reassigned`
	`77`	`+ // which means the return expression and parameters need to be reassigned`
`78`	`78`	`this.scope.getReturnExpression().deoptimizePath(UNKNOWN_PATH);`
	`79`	`+ for (const parameterList of this.scope.parameters) {`
	`80`	`+ for (const parameter of parameterList) {`
	`81`	`+ parameter.deoptimizePath(UNKNOWN_PATH);`
	`82`	`+ }`
	`83`	`+ }`
`79`	`84`	`}`
`80`	`85`	`}`
`81`	`86`