Add ReScript support

packages/reason-relay/language-plugin/src/@typings/graphql.ts

@@ -0,0 +1,5 @@
+import "graphql";
+
+declare module "graphql" {
+  const stripIgnoredCharacters: (source: string) => string;
+}

packages/reason-relay/language-plugin/src/@typings/relay-compiler.d.ts

@@ -0,0 +1,14 @@
+import { DefinitionNode, DocumentNode } from "graphql";
+import "relay-compiler";
+import { Fragment, Parser, Root, Schema } from "relay-compiler";
+
+declare module "relay-compiler" {
+  const convertASTDocuments: (
+    extendedSchema: Schema,
+    ast: DocumentNode[],
+    parser: (
+      schema: Schema,
+      documents: DefinitionNode[]
+    ) => readonly (Root | Fragment)[]
+  ) => readonly (Fragment | Root)[];
+}

packages/reason-relay/language-plugin/src/FindGraphQLTags.ts

@@ -3,12 +3,12 @@ import { GraphQLTag } from "relay-compiler/lib/language/RelayLanguagePluginInter
 const invariant = require("invariant");
 
 function parseFile(text: string, file: string) {
-  if (!text.includes("[%relay.")) {
+  if (!text.includes("[%relay.") && !text.includes("%relay.")) {
     return [];
   }
 
   invariant(
-    text.indexOf("[%relay.") >= 0,
+    text.indexOf("[%relay.") >= 0 || text.indexOf("%relay.") >= 0,
     "RelayFileIRParser: Files should be filtered before passed to the " +
       "parser, got unfiltered file `%s`.",
     file
@@ -19,19 +19,32 @@ function parseFile(text: string, file: string) {
    * regexp, but this will do just to get things working.
    */
 
-  const matched = text.match(
+  const matchedReason = text.match(
     /(?<=\[%relay\.(query|fragment|mutation|subscription))([\s\S]*?)(?=];)/g
   );
 
-  if (matched) {
+  if (matchedReason) {
     // Removes {||} used in multiline Reason strings
-    return matched.map(text => ({
+    return matchedReason.map(text => ({
       template: text.replace(/({\||\|})/g, ""),
       keyName: null,
       sourceLocationOffset: { line: 1, column: 1 }
     }));
   }
 
+  const matchedReScript = text.match(
+    /(?<=%relay\.(query|fragment|mutation|subscription)\()([\s\S]*?)(?=(\`\s*)\))(\`)/g
+  );
+
+  if (matchedReScript) {
+    // Removes `` used in multiline ReScript strings
+    return matchedReScript.map(text => ({
+      template: text.replace(/`/g, ""),
+      keyName: null,
+      sourceLocationOffset: { line: 1, column: 1 }
+    }));
+  }
+
   return [];
 }
 

packages/reason-relay/language-plugin/src/__tests__/FindGraphQLTags-tests.ts

@@ -0,0 +1,74 @@
+import { stripIgnoredCharacters } from "graphql";
+import { join, resolve } from "path";
+import { SourceLocation } from "relay-compiler/lib/core/IR";
+import { find } from "../FindGraphQLTags";
+import {
+  generateRelaySchema,
+  generateSchema,
+  parseGraphQLText,
+} from "../test-utils";
+
+const relaySchema = generateRelaySchema(
+  generateSchema(
+    resolve(join(__dirname, "..", "test-utils", "testSchema.graphql"))
+  )
+);
+
+const fragment = `
+fragment SomeComponent_user on User {
+  id
+}
+`;
+
+const query = `
+query appQuery($userId: ID!) {
+  user(id: $userId) {
+    id
+    firstName
+  }
+}
+`;
+
+describe("Language plugin tests", () => {
+  describe("RelayFindGraphQLTags", () => {
+    describe("ReScript Syntax", () => {
+      it("parses graphql templates", () => {
+        const graphqlTags = find(
+          `
+            module Fragment = %relay.fragment(
+              \`
+                ${fragment}
+              \`
+            )
+
+            module Query = %relay.query(
+              \`
+                ${query}
+              \`
+            )
+          `,
+          "test"
+        );
+
+        const parsedBodies = graphqlTags.map((tag) => {
+          const { definitions, schema } = parseGraphQLText(
+            relaySchema,
+            tag.template
+          );
+
+          return definitions && definitions.length && schema
+            ? stripIgnoredCharacters(
+                ((definitions[0] as any).loc as SourceLocation).source.body
+              )
+            : undefined;
+        });
+
+        expect(parsedBodies).toEqual([
+          stripIgnoredCharacters(fragment),
+          stripIgnoredCharacters(query),
+        ]);
+      });
+      // describe("ReScript Syntax", () => {});
+    });
+  });
+});