Relax TS version requirement to include older versions

This tests with TS 4.1, and Rollup 2.55, which are the lowest versions
that work without too much snapshot changes.
(Rollup could probably go lower, but they changed from `export default Foo` to `export { Foo as default }`)

fixes #176

.github/workflows/ci.yml

@@ -27,3 +27,7 @@ jobs:
         timeout-minutes: 1
         continue-on-error: true
         run: bash <(curl -s https://codecov.io/bash) -t ${{secrets.CODECOV_TOKEN}} -B ${{ github.ref }} -f coverage/coverage-final.json
+      # test the minimum supported peer dependency version
+      - run: npm install [email protected] [email protected]
+      # aka `npm test` without the `pretest/build`
+      - run: node .build/tests/index.js

package.json

@@ -52,17 +52,17 @@
     "@types/d3-drag": "^3.0.1",
     "@types/estree": "0.0.50",
     "@types/fs-extra": "^9.0.13",
-    "@types/node": "^16.11.10",
-    "@types/react": "^17.0.37",
+    "@types/node": "^17.0.4",
+    "@types/react": "^17.0.38",
     "c8": "^7.10.0",
     "fs-extra": "^10.0.0",
     "rimraf": "^3.0.2",
-    "rollup": "2.60.1",
-    "typescript": "4.5.2"
+    "rollup": "2.62.0",
+    "typescript": "4.5.4"
   },
   "peerDependencies": {
-    "rollup": "^2.60.1",
-    "typescript": "^4.5.2"
+    "rollup": "^2.55",
+    "typescript": "~4.1 || ~4.2 || ~4.3 || ~4.4 || ~4.5"
   },
   "optionalDependencies": {
     "@babel/code-frame": "^7.16.0"

tests/testcases.ts

@@ -2,6 +2,7 @@ import * as assert from "assert";
 import fsExtra from "fs-extra";
 import * as path from "path";
 import { InputOption, InputOptions, rollup, RollupOptions, RollupOutput } from "rollup";
+import ts from "typescript";
 import dts, { Options } from "../src/index.js";
 import { forEachFixture, Harness } from "./utils.js";
 
@@ -21,6 +22,15 @@ export default (t: Harness) => {
         meta.rollupOptions = Object.assign(rollupOptions, meta.rollupOptions);
       } catch {}
 
+      if (meta.tsVersion) {
+        const [major, minor] = ts.versionMajorMinor.split(".").map(Number);
+        const [reqMajor, reqMinor] = meta.tsVersion.split(".").map(Number);
+        if (major! < reqMajor! || minor! < reqMinor!) {
+          // skip unsupported version
+          return;
+        }
+      }
+
       if (!meta.skip) {
         return assertTestcase(dir, meta, bless);
       }
@@ -33,6 +43,7 @@ interface Meta {
   rollupOptions: RollupOptions;
   skip: boolean;
   expectedError?: string;
+  tsVersion?: string;
 }
 
 async function createBundle(options: Options, rollupOptions: RollupOptions) {

tests/testcases/ts42-abstract/meta.js

@@ -0,0 +1,3 @@
+export default {
+  tsVersion: "4.2",
+};

tests/testcases/ts43-getset/meta.js

@@ -0,0 +1,3 @@
+export default {
+  tsVersion: "4.2",
+};