[FindGraphQLTags] Add first test.

Author: alloy

src/FindGraphQLTags.ts

@@ -170,7 +170,7 @@ function getSourceLocationOffset(quasi: ts.TaggedTemplateExpression) {
   const pos = getTemplateNode(quasi).pos;
   const loc = quasi.getSourceFile().getLineAndCharacterOfPosition(pos);
   return {
-    line: loc.line + 1,
+    line: loc.line,
     column: loc.character + 1
   };
 }

test/FindGraphQLTags-test.ts

@@ -0,0 +1,31 @@
+import * as FindGraphQLTags from '../src/FindGraphQLTags'
+
+describe('FindGraphQLTags', () => {
+  function find(text) {
+    return FindGraphQLTags.find(text, '/path/to/TestModule.ts')
+  }
+
+  it('extracts a tag', () => {
+    expect(find(`
+      import { createFragmentContainer, graphql } from 'react-relay'
+      export default createFragmentContainer(
+        props => <div>{props.artist.name}</div>,
+        graphql\`
+          fragment TestModule_artist on Artist {
+            name
+          }
+        \`
+      )
+    `)).toEqual([{
+      keyName: null,
+      template: `
+          fragment TestModule_artist on Artist {
+            name
+          }
+        `,
+      sourceLocationOffset: { line: 4, column: 16 },
+    }])
+  })
+
+  // TODO: Cover all cases where tags are extracted
+})