Cherry-pick PR #49157 into release-4.7 (#49167)

Component commits: 8d1095d Fix uncalled function check usage detection for && expressions Co-authored-by: Andrew Branch <andrew@wheream.io>
microsoft · May 18, 2022 · 114e310 · 114e310
1 parent 77b83f1
commit 114e310
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Showing 6 changed files with 38 additions and 3 deletions.
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
@@ -37919,7 +37919,7 @@ namespace ts {
                     const childSymbol = getSymbolAtLocation(childNode);
                     if (childSymbol && childSymbol === testedSymbol) {
                         // If the test was a simple identifier, the above check is sufficient
-                        if (isIdentifier(expr)) {
+                        if (isIdentifier(expr) || isIdentifier(testedNode) && isBinaryExpression(testedNode.parent)) {
                             return true;
                         }
                         // Otherwise we need to ensure the symbol is called on the same target

diff --git a/tests/baselines/reference/uncalledFunctionChecksInConditional.errors.txt b/tests/baselines/reference/uncalledFunctionChecksInConditional.errors.txt
@@ -78,4 +78,8 @@ tests/cases/compiler/uncalledFunctionChecksInConditional.ts(48,22): error TS2774
 !!! error TS2774: This condition will always return true since this function is always defined. Did you mean to call it instead?
         // error on isFoo
     }
-
+
+    if (x && z) {
+        // no error
+        z();
+    }
diff --git a/tests/baselines/reference/uncalledFunctionChecksInConditional.js b/tests/baselines/reference/uncalledFunctionChecksInConditional.js
@@ -49,7 +49,11 @@ if (x || uy || z || isUndefinedFoo) {
 if (ux || y || uz || isFoo) {
     // error on isFoo
 }
-
+
+if (x && z) {
+    // no error
+    z();
+}
 
 //// [uncalledFunctionChecksInConditional.js]
 if (isFoo) {
@@ -82,3 +86,7 @@ if (x || uy || z || isUndefinedFoo) {
 if (ux || y || uz || isFoo) {
     // error on isFoo
 }
+if (x && z) {
+    // no error
+    z();
+}
diff --git a/tests/baselines/reference/uncalledFunctionChecksInConditional.symbols b/tests/baselines/reference/uncalledFunctionChecksInConditional.symbols
@@ -101,3 +101,11 @@ if (ux || y || uz || isFoo) {
     // error on isFoo
 }
 
+if (x && z) {
+>x : Symbol(x, Decl(uncalledFunctionChecksInConditional.ts, 24, 13))
+>z : Symbol(z, Decl(uncalledFunctionChecksInConditional.ts, 27, 38))
+
+    // no error
+    z();
+>z : Symbol(z, Decl(uncalledFunctionChecksInConditional.ts, 27, 38))
+}
diff --git a/tests/baselines/reference/uncalledFunctionChecksInConditional.types b/tests/baselines/reference/uncalledFunctionChecksInConditional.types
@@ -120,3 +120,13 @@ if (ux || y || uz || isFoo) {
     // error on isFoo
 }
 
+if (x && z) {
+>x && z : false | (() => boolean)
+>x : boolean
+>z : () => boolean
+
+    // no error
+    z();
+>z() : boolean
+>z : () => boolean
+}
diff --git a/tests/cases/compiler/uncalledFunctionChecksInConditional.ts b/tests/cases/compiler/uncalledFunctionChecksInConditional.ts
@@ -50,3 +50,8 @@ if (x || uy || z || isUndefinedFoo) {
 if (ux || y || uz || isFoo) {
     // error on isFoo
 }
+
+if (x && z) {
+    // no error
+    z();
+}