Allow fragments to be imported by name when using the webpack loader

Any packages that use graphql-tag/loader under the hood will also benefit.

README.md

@@ -137,6 +137,32 @@ And in your JavaScript:
 import { MyQuery1, MyQuery2 } from 'query.gql'
 ```
 
+#### Support for fragments
+
+With the webpack loader, you can import fragments by name:
+
+In a file called `query.gql`:
+```graphql
+fragment MyFragment1 on MyType1 {
+  ...
+}
+
+fragment MyFragment2 on MyType2 {
+  ...
+}
+```
+
+And in your JavaScript:
+
+```javascript
+import { MyFragment1, MyFragment2 } from 'query.gql'
+```
+
+Note: If your fragment references other fragments, the resulting document will
+have multiple fragments in it.  In this case you must still specify the fragment
+name when using the fragment.  For example, with `apollo-client` you would specify
+the `fragmentName` option when using the fragment for cache operations. 
+
 ### Warnings
 
 This package will emit a warning if you have multiple fragments of the same name. You can disable this with:

loader.js

@@ -53,7 +53,7 @@ module.exports = function(source) {
   // at compile time, and then uses those at load time to create minimal query documents
   // We cannot do the latter at compile time due to how the #import code works.
   let operationCount = doc.definitions.reduce(function(accum, op) {
-    if (op.kind === "OperationDefinition") {
+    if (op.kind === "OperationDefinition" || op.kind === "FragmentDefinition") {
       return accum + 1;
     }
 
@@ -161,12 +161,12 @@ module.exports = function(source) {
 
       return newDoc;
     }
-
-    module.exports = doc;
+    
+    module.exports = Object.assign({default: doc}, doc);
     `
 
     for (const op of doc.definitions) {
-      if (op.kind === "OperationDefinition") {
+      if (op.kind === "OperationDefinition" || op.kind === "FragmentDefinition") {
         if (!op.name) {
           if (operationCount > 1) {
             throw "Query/mutation names are required for a document with multiple definitions";

test/graphql.js

@@ -92,7 +92,7 @@ const assert = require('chai').assert;
 
       gql.disableExperimentalFragmentVariables()
     });
-    
+
     // see https://github.com/apollographql/graphql-tag/issues/168
     it('does not nest queries needlessly in named exports', () => {
       const jsSource = loader.call({ cacheable() {} }, `
@@ -143,6 +143,17 @@ const assert = require('chai').assert;
       assert.equal(Q3[1].name.value, 'F1');
       assert.equal(Q3[2].name.value, 'F2');
 
+      const F1 = module.exports.F1.definitions;
+      const F2 = module.exports.F2.definitions;
+      const F3 = module.exports.F3.definitions;
+
+      assert.equal(F1.length, 1);
+      assert.equal(F1[0].name.value, 'F1');
+      assert.equal(F2.length, 1);
+      assert.equal(F2[0].name.value, 'F2');
+      assert.equal(F3.length, 1);
+      assert.equal(F3[0].name.value, 'F3');
+
     });
 
     it('tracks fragment dependencies across nested fragments', () => {
@@ -182,6 +193,20 @@ const assert = require('chai').assert;
       assert.equal(Q1[3].name.value, 'F11');
 
       assert.equal(Q2.length, 1);
+
+      const F11 = module.exports.F11.definitions;
+      const F22 = module.exports.F22.definitions;
+      const F33 = module.exports.F33.definitions;
+
+      assert.equal(F11.length, 1);
+      assert.equal(F11[0].name.value, 'F11');
+      assert.equal(F22.length, 2);
+      assert.equal(F22[0].name.value, 'F22');
+      assert.equal(F22[1].name.value, 'F11');
+      assert.equal(F33.length, 3);
+      assert.equal(F33[0].name.value, 'F33');
+      assert.equal(F33[1].name.value, 'F22');
+      assert.equal(F33[2].name.value, 'F11');
     });
 
     it('correctly imports other files through the webpack loader', () => {