feat: add PURE annotations for bundlers

gajus · May 19, 2021 · c49e30d · c49e30d
2 parents a3a15d4 + fd62d7c
commit c49e30d
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Showing 3 changed files with 11 additions and 2 deletions.
diff --git a/src/index.js b/src/index.js
@@ -11,6 +11,7 @@ import {stripIgnoredCharacters} from 'graphql';
 
 const debug = createDebug('babel-plugin-graphql-tag');
 const {
+  addComment,
   cloneDeep,
   isIdentifier,
   isMemberExpression,
@@ -24,6 +25,8 @@ const {
   isObjectPattern,
 } = types;
 
+const PURE_ANNOTATION = '#__PURE__';
+
 // eslint-disable-next-line no-restricted-syntax
 const uniqueFn = parseExpression(`
   (definitions) => {
@@ -109,6 +112,12 @@ export default declare((api, options) => {
 
       definitionsProperty.value = callExpression(uniqueId, [allDefinitions]);
 
+      // Marking these function calls with an annotation indicating that
+      // they're pure will allow bundlers like Webpack and Rollup to more
+      // aggressively remove unused queries from bundles.
+      addComment(allDefinitions, 'leading', PURE_ANNOTATION);
+      addComment(definitionsProperty.value, 'leading', PURE_ANNOTATION);
+
       uniqueUsed = true;
     }
 

diff --git a/test/fixtures/apollov3/converts inline gql tag with fragment interpolation/output.mjs b/test/fixtures/apollov3/converts inline gql tag with fragment interpolation/output.mjs
@@ -122,7 +122,7 @@ const baz = {
 };
 const foo = {
   "kind": "Document",
-  "definitions": _unique([{
+  "definitions": /*#__PURE__*/_unique( /*#__PURE__*/[{
     "kind": "OperationDefinition",
     "operation": "query",
     "name": {

diff --git a/test/fixtures/graphql-tag/converts inline gql tag with fragment interpolation/output.mjs b/test/fixtures/graphql-tag/converts inline gql tag with fragment interpolation/output.mjs
@@ -122,7 +122,7 @@ const baz = {
 };
 const foo = {
   "kind": "Document",
-  "definitions": _unique([{
+  "definitions": /*#__PURE__*/_unique( /*#__PURE__*/[{
     "kind": "OperationDefinition",
     "operation": "query",
     "name": {