Escape apparent substitution in synthesized NoSubstitutionTemplateLiterals (microsoft#32580)

andrewbranch · web-flow · commit c1e0db7953e0 · 2019-08-05T09:31:59.000-07:00
* Add failing test

* Escape apparent substitution in synthesized NoSubstitutionTemplateLiterals
diff --git a/src/compiler/utilities.ts b/src/compiler/utilities.ts
@@ -566,6 +566,8 @@ namespace ts {
         return emitNode && emitNode.flags || 0;
     }
 
+    const escapeNoSubstitutionTemplateLiteralText = compose(escapeString, escapeTemplateSubstitution);
+    const escapeNonAsciiNoSubstitutionTemplateLiteralText = compose(escapeNonAsciiString, escapeTemplateSubstitution);
     export function getLiteralText(node: LiteralLikeNode, sourceFile: SourceFile, neverAsciiEscape: boolean | undefined) {
         // If we don't need to downlevel and we can reach the original source text using
         // the node's parent reference, then simply get the text as it was originally written.
@@ -576,7 +578,11 @@ namespace ts {
             return getSourceTextOfNodeFromSourceFile(sourceFile, node);
         }
 
-        const escapeText = neverAsciiEscape || (getEmitFlags(node) & EmitFlags.NoAsciiEscaping) ? escapeString : escapeNonAsciiString;
+        // If a NoSubstitutionTemplateLiteral appears to have a substitution in it, the original text
+        // had to include a backslash: `not \${a} substitution`.
+        const escapeText = neverAsciiEscape || (getEmitFlags(node) & EmitFlags.NoAsciiEscaping) ?
+            node.kind === SyntaxKind.NoSubstitutionTemplateLiteral ? escapeNoSubstitutionTemplateLiteralText : escapeString :
+            node.kind === SyntaxKind.NoSubstitutionTemplateLiteral ? escapeNonAsciiNoSubstitutionTemplateLiteralText : escapeNonAsciiString;
 
         // If we can't reach the original source text, use the canonical form if it's a number,
         // or a (possibly escaped) quoted form of the original text if it's string-like.
@@ -3113,6 +3119,11 @@ namespace ts {
         }
     }
 
+    const templateSubstitutionRegExp = /\$\{/g;
+    function escapeTemplateSubstitution(str: string): string {
+        return str.replace(templateSubstitutionRegExp, "\\${");
+    }
+
     // This consists of the first 19 unprintable ASCII characters, canonical escapes, lineSeparator,
     // paragraphSeparator, and nextLine. The latter three are just desirable to suppress new lines in
     // the language service. These characters should be escaped when printing, and if any characters are added,
diff --git a/tests/cases/fourslash/refactorConvertParamsToDestructuredObject_templateLiteral.ts b/tests/cases/fourslash/refactorConvertParamsToDestructuredObject_templateLiteral.ts
@@ -0,0 +1,16 @@
+/// <reference path='fourslash.ts' />
+
+////function /*a*/insert/*b*/(template: string, overwriteBefore = 0) {}
+////insert(`this is \${not} a substitution`);
+
+
+goTo.select("a", "b");
+edit.applyRefactor({
+    refactorName: "Convert parameters to destructured object",
+    actionName: "Convert parameters to destructured object",
+    actionDescription: "Convert parameters to destructured object",
+    newContent: [
+      'function insert({ template, overwriteBefore = 0 }: { template: string; overwriteBefore?: number; }) {}',
+      'insert({ template: `this is \\${not} a substitution` });'
+    ].join('\n')
+});
