constant-folding: Fix some literal types used in .join()

babel · Jul 2, 2017 · b820250 · b820250
1 parent 64bb89f
commit b820250
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Showing 2 changed files with 16 additions and 4 deletions.
diff --git a/packages/babel-plugin-minify-constant-folding/__tests__/constant-folding-test.js b/packages/babel-plugin-minify-constant-folding/__tests__/constant-folding-test.js
@@ -103,6 +103,9 @@ describe("constant-folding-plugin", () => {
     [1, 2, 3].join();
     ["a", "b", "c"].join();
     ["a", "b", "c"].join("@");
+    [null, 1].join("/");
+    [/xyz/im, true].join("abc");
+    [\`a\${xyz}\`].join("1");
 
     [1, 2, 3].length;
     [1, 2, 3][1];
@@ -134,6 +137,9 @@ describe("constant-folding-plugin", () => {
     "1,2,3";
     "a,b,c";
     "a@b@c";
+    "/1";
+    "/xyz/imabctrue";
+    [\`a\${xyz}\`].join("1");
 
     3;
     2;

diff --git a/packages/babel-plugin-minify-constant-folding/src/replacements.js b/packages/babel-plugin-minify-constant-folding/src/replacements.js
@@ -43,11 +43,17 @@ module.exports = ({ types: t }) => {
           let bad = false;
           const str = this.elements
             .map(el => {
-              if (!t.isLiteral(el)) {
-                bad = true;
-                return;
+              if (t.isRegExpLiteral(el)) {
+                return `/${el.pattern}/${el.flags}`;
               }
-              return el.value;
+              if (t.isNullLiteral(el)) {
+                return null;
+              }
+              if (t.isStringLiteral(el) || t.isBooleanLiteral(el) || t.isNumericLiteral(el)) {
+                return el.value;
+              }
+              bad = true;
+              return;
             })
             .join(sep.value);
           return bad ? undefined : t.stringLiteral(str);