Add preceding semicolon on await insertion when parentheses are included (microsoft#34627)

* Add preceding semicolon on await insertion when parentheses are included

* Just start with precedingToken

* Fix semicolon formatter regression

* Delete test with debatable expected behavior

* Lint after control flow changes

Author: andrewbranch

src/harness/fourslash.ts

@@ -2358,9 +2358,9 @@ namespace FourSlash {
             if (!details) {
                 return this.raiseError(`No completions were found for the given name, source, and preferences.`);
             }
-            const codeActions = details.codeActions!;
-            if (codeActions.length !== 1) {
-                this.raiseError(`Expected one code action, got ${codeActions.length}`);
+            const codeActions = details.codeActions;
+            if (codeActions?.length !== 1) {
+                this.raiseError(`Expected one code action, got ${codeActions?.length ?? 0}`);
             }
             const codeAction = ts.first(codeActions);
 

src/services/codefixes/addMissingAwait.ts

@@ -257,6 +257,7 @@ namespace ts.codefix {
                 sourceFile,
                 insertionSite.parent.expression,
                 createParen(createAwait(insertionSite.parent.expression)));
+            insertLeadingSemicolonIfNeeded(changeTracker, insertionSite.parent.expression, sourceFile);
         }
         else if (contains(callableConstructableErrorCodes, errorCode) && isCallOrNewExpression(insertionSite.parent)) {
             if (fixedDeclarations && isIdentifier(insertionSite)) {
@@ -266,6 +267,7 @@ namespace ts.codefix {
                 }
             }
             changeTracker.replaceNode(sourceFile, insertionSite, createParen(createAwait(insertionSite)));
+            insertLeadingSemicolonIfNeeded(changeTracker, insertionSite, sourceFile);
         }
         else {
             if (fixedDeclarations && isVariableDeclaration(insertionSite.parent) && isIdentifier(insertionSite.parent.name)) {
@@ -277,4 +279,11 @@ namespace ts.codefix {
             changeTracker.replaceNode(sourceFile, insertionSite, createAwait(insertionSite));
         }
     }
+
+    function insertLeadingSemicolonIfNeeded(changeTracker: textChanges.ChangeTracker, beforeNode: Node, sourceFile: SourceFile) {
+        const precedingToken = findPrecedingToken(beforeNode.pos, sourceFile);
+        if (precedingToken && positionIsASICandidate(precedingToken.end, precedingToken.parent, sourceFile)) {
+            changeTracker.insertText(sourceFile, beforeNode.getStart(sourceFile), ";");
+        }
+    }
 }

src/services/completions.ts

@@ -373,7 +373,13 @@ namespace ts.Completions {
         }
         if (origin && originIsPromise(origin) && propertyAccessToConvert) {
             if (insertText === undefined) insertText = name;
-            const awaitText = `(await ${propertyAccessToConvert.expression.getText()})`;
+            const precedingToken = findPrecedingToken(propertyAccessToConvert.pos, sourceFile);
+            let awaitText = "";
+            if (precedingToken && positionIsASICandidate(precedingToken.end, precedingToken.parent, sourceFile)) {
+                awaitText = ";";
+            }
+
+            awaitText += `(await ${propertyAccessToConvert.expression.getText()})`;
             insertText = needsConvertPropertyAccess ? `${awaitText}${insertText}` : `${awaitText}${insertQuestionDot ? "?." : "."}${insertText}`;
             replacementSpan = createTextSpanFromBounds(propertyAccessToConvert.getStart(sourceFile), propertyAccessToConvert.end);
         }

src/services/formatting/rules.ts

@@ -855,13 +855,6 @@ namespace ts.formatting {
     }
 
     function isSemicolonInsertionContext(context: FormattingContext): boolean {
-        const contextAncestor = findAncestor(context.currentTokenParent, ancestor => {
-            if (ancestor.end !== context.currentTokenSpan.end) {
-                return "quit";
-            }
-            return syntaxMayBeASICandidate(ancestor.kind);
-        });
-
-        return !!contextAncestor && isASICandidate(contextAncestor, context.sourceFile);
+        return positionIsASICandidate(context.currentTokenSpan.end, context.currentTokenParent, context.sourceFile);
     }
 }

src/services/utilities.ts

@@ -2066,7 +2066,7 @@ namespace ts {
         syntaxRequiresTrailingModuleBlockOrSemicolonOrASI,
         syntaxRequiresTrailingSemicolonOrASI);
 
-    export function isASICandidate(node: Node, sourceFile: SourceFileLike): boolean {
+    function nodeIsASICandidate(node: Node, sourceFile: SourceFileLike): boolean {
         const lastToken = node.getLastToken(sourceFile);
         if (lastToken && lastToken.kind === SyntaxKind.SemicolonToken) {
             return false;
@@ -2109,6 +2109,17 @@ namespace ts {
         return startLine !== endLine;
     }
 
+    export function positionIsASICandidate(pos: number, context: Node, sourceFile: SourceFileLike): boolean {
+        const contextAncestor = findAncestor(context, ancestor => {
+            if (ancestor.end !== pos) {
+                return "quit";
+            }
+            return syntaxMayBeASICandidate(ancestor.kind);
+        });
+
+        return !!contextAncestor && nodeIsASICandidate(contextAncestor, sourceFile);
+    }
+
     export function probablyUsesSemicolons(sourceFile: SourceFile): boolean {
         let withSemicolon = 0;
         let withoutSemicolon = 0;

tests/cases/fourslash/codeFixAddMissingAwait_propertyAccess2.ts

@@ -0,0 +1,15 @@
+/// <reference path="fourslash.ts" />
+////async function fn(a: Promise<{ x: string }>) {
+////  console.log(3)
+////  a.x;
+////}
+
+verify.codeFix({
+  description: ts.Diagnostics.Add_await.message,
+  index: 0,
+  newFileContent:
+`async function fn(a: Promise<{ x: string }>) {
+  console.log(3)
+  ;(await a).x;
+}`
+});

tests/cases/fourslash/codeFixAddMissingAwait_signatures2.ts

@@ -0,0 +1,50 @@
+/// <reference path="fourslash.ts" />
+////async function fn(a: Promise<() => void>, b: Promise<() => void> | (() => void), C: Promise<{ new(): any }>) {
+////  a()
+////  b()
+////  new C()
+////}
+
+verify.codeFix({
+  description: ts.Diagnostics.Add_await.message,
+  index: 0,
+  newFileContent:
+`async function fn(a: Promise<() => void>, b: Promise<() => void> | (() => void), C: Promise<{ new(): any }>) {
+  (await a)()
+  b()
+  new C()
+}`
+});
+
+verify.codeFix({
+  description: ts.Diagnostics.Add_await.message,
+  index: 1,
+  newFileContent:
+`async function fn(a: Promise<() => void>, b: Promise<() => void> | (() => void), C: Promise<{ new(): any }>) {
+  a()
+  ;(await b)()
+  new C()
+}`
+});
+
+verify.codeFix({
+  description: ts.Diagnostics.Add_await.message,
+  index: 2,
+  newFileContent:
+`async function fn(a: Promise<() => void>, b: Promise<() => void> | (() => void), C: Promise<{ new(): any }>) {
+  a()
+  b()
+  new (await C)()
+}`
+});
+
+verify.codeFixAll({
+  fixAllDescription: ts.Diagnostics.Fix_all_expressions_possibly_missing_await.message,
+  fixId: "addMissingAwait",
+  newFileContent:
+`async function fn(a: Promise<() => void>, b: Promise<() => void> | (() => void), C: Promise<{ new(): any }>) {
+  (await a)()
+  ;(await b)()
+  new (await C)()
+}`
+});

tests/cases/fourslash/completionOfAwaitPromise7.ts

@@ -0,0 +1,18 @@
+/// <reference path='fourslash.ts'/>
+
+////async function foo(x: Promise<string>) {
+////    console.log
+////    [|x./**/|]
+////}
+
+const replacementSpan = test.ranges()[0];
+verify.completions({
+    marker: "",
+    includes: [
+        "then",
+        { name: "trim", insertText: ';(await x).trim', replacementSpan },
+    ],
+    preferences: {
+        includeInsertTextCompletions: true,
+    },
+});