Fix bug for isValidTrigger when contextToken is undefined (microsoft#25993)

Andy · web-flow · commit af3f73745145 · 2018-07-26T17:26:58.000-07:00
diff --git a/src/services/completions.ts b/src/services/completions.ts
@@ -42,7 +42,7 @@ namespace ts.Completions {
         }
 
         const contextToken = findPrecedingToken(position, sourceFile);
-        if (triggerCharacter && !isValidTrigger(sourceFile, triggerCharacter, contextToken!, position)) return undefined; // TODO: GH#18217
+        if (triggerCharacter && (!contextToken || !isValidTrigger(sourceFile, triggerCharacter, contextToken, position))) return undefined;
 
         if (isInString(sourceFile, position, contextToken)) {
             return !contextToken || !isStringLiteralLike(contextToken)
diff --git a/tests/cases/fourslash/completionsTriggerCharacter.ts b/tests/cases/fourslash/completionsTriggerCharacter.ts
@@ -2,6 +2,7 @@
 
 // @jsx: preserve
 
+//////</*comment*/
 ////const x: "a" | "b" = "/*openQuote*/"/*closeQuote*/;
 ////const y: 'a' | 'b' = '/*openSingleQuote*/'/*closeSingleQuote*/;
 ////const z: 'a' | 'b' = `/*openTemplate*/`/*closeTemplate*/;
@@ -28,6 +29,8 @@
 ////const divide = 1 //*divide*/
 
 verify.completions(
+    { marker: "comment", exact: undefined, triggerCharacter: "<" },
+
     { marker: "openQuote", exact: ["a", "b"], triggerCharacter: '"' },
     { marker: "closeQuote", exact: undefined, triggerCharacter: '"' },
 

Original file line number	Diff line number	Diff line change
`@@ -42,7 +42,7 @@ namespace ts.Completions {`
`42`	`42`	`}`
`43`	`43`
`44`	`44`	`const contextToken = findPrecedingToken(position, sourceFile);`
`45`		`- if (triggerCharacter && !isValidTrigger(sourceFile, triggerCharacter, contextToken!, position)) return undefined; // TODO: GH#18217`
	`45`	`+ if (triggerCharacter && (!contextToken \|\| !isValidTrigger(sourceFile, triggerCharacter, contextToken, position))) return undefined;`
`46`	`46`
`47`	`47`	`if (isInString(sourceFile, position, contextToken)) {`
`48`	`48`	`return !contextToken \|\| !isStringLiteralLike(contextToken)`