allow additional arguments to feature functions

Author: mbostock

src/javascript/__snapshots__/databases.test.ts.snap

@@ -0,0 +1,84 @@
+// Vitest Snapshot v1, https://vitest.dev/guide/snapshot.html
+
+exports[`allows additional arguments 1`] = `
+[
+  Node {
+    "argument": "foo",
+    "arguments": [
+      Node {
+        "end": 20,
+        "raw": ""foo"",
+        "start": 15,
+        "type": "Literal",
+        "value": "foo",
+      },
+      Node {
+        "end": 57,
+        "properties": [
+          Node {
+            "computed": false,
+            "end": 56,
+            "key": Node {
+              "end": 28,
+              "name": "since",
+              "start": 23,
+              "type": "Identifier",
+            },
+            "kind": "init",
+            "method": false,
+            "shorthand": false,
+            "start": 23,
+            "type": "Property",
+            "value": Node {
+              "end": 56,
+              "raw": ""2021-01-01T12:34:56.789Z"",
+              "start": 30,
+              "type": "Literal",
+              "value": "2021-01-01T12:34:56.789Z",
+            },
+          },
+        ],
+        "start": 22,
+        "type": "ObjectExpression",
+      },
+    ],
+    "callee": Node {
+      "end": 14,
+      "name": "DatabaseClient",
+      "start": 0,
+      "type": "Identifier",
+    },
+    "end": 58,
+    "optional": false,
+    "start": 0,
+    "type": "CallExpression",
+  },
+]
+`;
+
+exports[`finds databases 1`] = `
+[
+  Node {
+    "argument": "foo",
+    "arguments": [
+      Node {
+        "end": 20,
+        "raw": ""foo"",
+        "start": 15,
+        "type": "Literal",
+        "value": "foo",
+      },
+    ],
+    "callee": Node {
+      "end": 14,
+      "name": "DatabaseClient",
+      "start": 0,
+      "type": "Identifier",
+    },
+    "end": 21,
+    "optional": false,
+    "start": 0,
+    "type": "CallExpression",
+  },
+]
+`;

src/javascript/databases.test.ts

@@ -0,0 +1,31 @@
+import {expect, test} from "vitest";
+import {parseJavaScript} from "./parse.js";
+import type {FeatureExpression} from "./features.js";
+
+function find(input: string): FeatureExpression[] {
+  return parseJavaScript(input).databases;
+}
+
+test("finds databases", () => {
+  expect(find(`DatabaseClient("foo")`)).toMatchSnapshot();
+});
+
+test("allows additional arguments", () => {
+  expect(find(`DatabaseClient("foo", {since: "2021-01-01T12:34:56.789Z"})`)).toMatchSnapshot();
+});
+
+test("disallows dynamic arguments", () => {
+  expect(() => find(`DatabaseClient("foo" + bar)`)).toThrow(/literal string/);
+});
+
+test("ignores shadowed references", () => {
+  expect(find(`const DatabaseClient = () => {};\nDatabaseClient("foo");`)).toStrictEqual([]);
+  expect(find(`DatabaseClient("foo");\nconst DatabaseClient = () => {};`)).toStrictEqual([]);
+  expect(find(`DatabaseClient("foo");\nvar DatabaseClient = () => {};`)).toStrictEqual([]);
+  expect(find(`function DatabaseClient() {}\nDatabaseClient("foo");`)).toStrictEqual([]);
+  expect(find(`function DatabaseClient() {}\nDatabaseClient("foo" + Math.random());`)).toStrictEqual([]); // prettier-ignore
+});
+
+test("ignores aliased references", () => {
+  expect(find(`const D = DatabaseClient;\nD("foo");`)).toStrictEqual([]);
+});

src/javascript/features.ts

@@ -20,10 +20,8 @@ export function findFeatures(name: string, body: Node, input: string): FeatureEx
     CallExpression(node) {
       const {callee} = node;
       if (callee.type !== "Identifier" || !references.has(callee)) return;
-      const args = node.arguments;
-      if (args.length !== 1) throw syntaxError(`${name} requires a single literal string argument`, node, input); // prettier-ignore
-      const [arg] = args;
-      if (!isStringLiteral(arg)) throw syntaxError(`${name} requires a single literal string argument`, node, input); // prettier-ignore
+      const [arg] = node.arguments;
+      if (!arg || !isStringLiteral(arg)) throw syntaxError(`${name} requires a literal string argument`, node, input); // prettier-ignore
       calls.push(Object.assign(node, {argument: getStringLiteralValue(arg)}));
     }
   });