fix(49838): "Extract function" refactoring action is disabled for a wrong reason (#49840)

* fix(49838): allow extracting functions with a break statement inside loop context

* remove useless flag

* add more tests

Author: a-tarasyuk

src/services/refactors/extractSymbol.ts

@@ -551,7 +551,7 @@ namespace ts.refactor.extractSymbol {
                 const savedPermittedJumps = permittedJumps;
                 switch (node.kind) {
                     case SyntaxKind.IfStatement:
-                        permittedJumps = PermittedJumps.None;
+                        permittedJumps &= ~PermittedJumps.Return;
                         break;
                     case SyntaxKind.TryStatement:
                         // forbid all jumps inside try blocks

tests/cases/fourslash/extract-method45.ts

@@ -0,0 +1,54 @@
+/// <reference path="fourslash.ts" />
+
+////export function fn(m: number) {
+////    const mode = m >= 0 ? "a" : "b";
+////    let result: number = 0;
+////
+////    if (mode === "a") {
+////        /*a*/for (let i = 0; i < 10; i++) {
+////            const rand = Math.random();
+////            if (rand > 0.5) {
+////                result = rand;
+////                break;
+////            }
+////        }/*b*/
+////    }
+////    else {
+////        result = 0;
+////    }
+////
+////    return result;
+////}
+
+goTo.select("a", "b");
+edit.applyRefactor({
+    refactorName: "Extract Symbol",
+    actionName: "function_scope_1",
+    actionDescription: "Extract to function in module scope",
+    newContent:
+`export function fn(m: number) {
+    const mode = m >= 0 ? "a" : "b";
+    let result: number = 0;
+
+    if (mode === "a") {
+        result = /*RENAME*/newFunction(result);
+    }
+    else {
+        result = 0;
+    }
+
+    return result;
+}
+
+function newFunction(result: number) {
+    for (let i = 0; i < 10; i++) {
+        const rand = Math.random();
+        if (rand > 0.5) {
+            result = rand;
+            break;
+        }
+    }
+    return result;
+}
+`
+});

tests/cases/fourslash/extract-method46.ts

@@ -0,0 +1,54 @@
+/// <reference path="fourslash.ts" />
+
+////export function fn(m: number, n: number) {
+////    const mode = m >= 0 ? "a" : "b";
+////    let result: number = 0;
+////
+////    if (mode === "a") {
+////        /*a*/for (let i = 0; i < n; i++) {
+////            const rand = Math.random();
+////            if (rand > 0.5) {
+////                result = rand;
+////                break;
+////            }
+////        }/*b*/
+////    }
+////    else {
+////        result = 0;
+////    }
+////
+////    return result;
+////}
+
+goTo.select("a", "b");
+edit.applyRefactor({
+    refactorName: "Extract Symbol",
+    actionName: "function_scope_1",
+    actionDescription: "Extract to function in module scope",
+    newContent:
+`export function fn(m: number, n: number) {
+    const mode = m >= 0 ? "a" : "b";
+    let result: number = 0;
+
+    if (mode === "a") {
+        result = /*RENAME*/newFunction(n, result);
+    }
+    else {
+        result = 0;
+    }
+
+    return result;
+}
+
+function newFunction(n: number, result: number) {
+    for (let i = 0; i < n; i++) {
+        const rand = Math.random();
+        if (rand > 0.5) {
+            result = rand;
+            break;
+        }
+    }
+    return result;
+}
+`
+});

tests/cases/fourslash/extract-method47.ts

@@ -0,0 +1,60 @@
+/// <reference path="fourslash.ts" />
+
+////export function fn(m: number, n: number) {
+////    const mode = m >= 0 ? "a" : "b";
+////    let result: number = 0;
+////
+////    if (mode === "a") {
+////        /*a*/for (let i = 0; i < n; i++) {
+////            const rand = Math.random();
+////            switch (rand) {
+////                 case 0.5:
+////                     result = rand;
+////                     break;
+////                 default:
+////                     result = 1;
+////                     break;
+////            }
+////        }/*b*/
+////    }
+////    else {
+////        result = 0;
+////    }
+////    return result;
+////}
+
+goTo.select("a", "b");
+edit.applyRefactor({
+    refactorName: "Extract Symbol",
+    actionName: "function_scope_1",
+    actionDescription: "Extract to function in module scope",
+    newContent:
+`export function fn(m: number, n: number) {
+    const mode = m >= 0 ? "a" : "b";
+    let result: number = 0;
+
+    if (mode === "a") {
+        result = /*RENAME*/newFunction(n, result);
+    }
+    else {
+        result = 0;
+    }
+    return result;
+}
+
+function newFunction(n: number, result: number) {
+    for (let i = 0; i < n; i++) {
+        const rand = Math.random();
+        switch (rand) {
+            case 0.5:
+                result = rand;
+                break;
+            default:
+                result = 1;
+                break;
+        }
+    }
+    return result;
+}
+`
+});

tests/cases/fourslash/extract-method48.ts

@@ -0,0 +1,36 @@
+/// <reference path="fourslash.ts" />
+
+////export function fn(x: number, y: number) {
+////    /*a*/switch (x) {
+////        case 1:
+////            if (y) {
+////                break;
+////            }
+////            x--;
+////            break;
+////    }/*b*/
+////}
+
+goTo.select("a", "b");
+edit.applyRefactor({
+    refactorName: "Extract Symbol",
+    actionName: "function_scope_1",
+    actionDescription: "Extract to function in module scope",
+    newContent:
+`export function fn(x: number, y: number) {
+    x = /*RENAME*/newFunction(x, y);
+}
+
+function newFunction(x: number, y: number) {
+    switch (x) {
+        case 1:
+            if (y) {
+                break;
+            }
+            x--;
+            break;
+    }
+    return x;
+}
+`
+});