feat: add setupNinja

Used some code from https://github.com/aminya/install-cmake/blob/new-versions-and-arch/src/ninja.ts

action.yml

@@ -11,11 +11,12 @@ inputs:
     required: false
   cmake:
     description: "The cmake version to install."
-    default: '3.20.2'
+    default: "3.20.2"
     required: false
   ninja:
     description: "The ninja version to install."
-    required: false
+    default: "1.10.2"
+    required: true
 
 runs:
   using: "node12"

src/main.ts

@@ -1,13 +1,28 @@
 import * as core from "@actions/core"
 import { setupCmake } from "./cmake/cmake"
+import { setupNinja } from "./ninja/ninja"
+
+function maybeGetInput(key: string) {
+  const value = core.getInput(key)
+  if (value !== "false" && value !== "") {
+    return value
+  }
+  return undefined
+}
 
 export async function main(): Promise<number> {
   try {
     // setup cmake
-    const cmakeVersion = core.getInput("cmake")
-    if (cmakeVersion !== "false" && cmakeVersion !== "") {
+    const cmakeVersion = maybeGetInput("cmake")
+    if (cmakeVersion !== undefined) {
       await setupCmake(cmakeVersion)
     }
+
+    // setup ninja
+    const ninjaVersion = maybeGetInput("ninja")
+    if (ninjaVersion !== undefined) {
+      await setupNinja(ninjaVersion)
+    }
   } catch (err) {
     core.error(err as string | Error)
     core.setFailed("install-cpp failed")

src/ninja/ninja.ts

@@ -0,0 +1,46 @@
+import { extractZip, find, downloadTool, cacheFile } from "@actions/tool-cache"
+import { addPath, group, startGroup, endGroup } from "@actions/core"
+import { join } from "path"
+import { existsSync } from "fs"
+import * as hasha from "hasha"
+import { tmpdir } from "os"
+
+export async function setupNinja(version: string): Promise<string> {
+  const platform = process.platform
+
+  // Build artifact name
+  const ninjaBin = platform === "win32" ? "ninja.exe" : "ninja"
+
+  // Restore from cache (if found).
+  const ninjaDir = find("ninja", version)
+  if (ninjaDir) {
+    addPath(ninjaDir)
+    return join(ninjaDir, ninjaBin)
+  }
+
+  const url = `https://github.com/ninja-build/ninja/releases/download/v${version}/ninja-${platform}.zip`
+
+  // Get an unique output directory name from the URL.
+  const key: string = await hasha.async(url)
+  const outputDir = join(process.env.RUNNER_TEMP ?? tmpdir(), key)
+
+  const ninjaPath = join(outputDir, ninjaBin)
+
+  if (!existsSync(outputDir)) {
+    await group("Download and extract ninja-build", async () => {
+      const downloaded = await downloadTool(url)
+      await extractZip(downloaded, outputDir)
+    })
+  }
+
+  try {
+    startGroup("Add ninja-build to PATH")
+    addPath(outputDir)
+  } finally {
+    endGroup()
+  }
+
+  await cacheFile(ninjaPath, ninjaBin, "ninja", version)
+
+  return ninjaPath
+}