Use path library for path manipulation

Previously, this action relied heavily on string manipulation techniques
to compose paths. This approach is prone to error, particularly in the
context of Windows and inconsistent use of native path delimiters.

action/src/main.ts

@@ -40,7 +40,7 @@ const binlessToolDirectories = ["Conan", "Ninja"];
 
 const toolsPaths = (installDir: string): string[] => {
   const binlessPaths: string[] = binlessToolDirectories
-    .map((dir) => `${installDir}/Tools/${dir}`)
+    .map((dir) => path.join(installDir, "Tools", dir))
     .filter((dir) => dirExists(dir));
   return [
     "Tools/**/bin",
@@ -77,14 +77,16 @@ const locateQtArchDir = (installDir: string): string => {
   // This makes a list of all the viable arch directories that contain a qmake file.
   const qtArchDirs = glob
     .sync(`${installDir}/[0-9]*/*/bin/qmake*`)
-    .map((s) => s.replace(/\/bin\/qmake[^/]*$/, ""));
+    .map((s) => path.join(s, "..", ".."));
 
   // For Qt6 mobile and wasm installations, and Qt6 Windows on ARM installations,
   // a standard desktop Qt installation must exist alongside the requested architecture.
   // In these cases, we must select the first item that ends with 'android*', 'ios', 'wasm*' or 'msvc*_arm64'.
-  const requiresParallelDesktop = qtArchDirs.filter((p) =>
-    p.match(/6\.\d+\.\d+\/(android[^/]*|ios|wasm[^/]*|msvc[^/]*_arm64)$/)
-  );
+  const requiresParallelDesktop = qtArchDirs.filter((archPath) => {
+    const archDir = path.basename(archPath);
+    const versionDir = path.basename(path.join(archPath, ".."));
+    return versionDir.match(/^6\.\d+\.\d+$/) && archDir.match(/^(android*|ios|wasm*|msvc*_arm64)$/);
+  });
   if (requiresParallelDesktop.length) {
     // NOTE: if multiple mobile/wasm installations coexist, this may not select the desired directory
     return requiresParallelDesktop[0];
@@ -204,7 +206,7 @@ class Inputs {
     if (!dir) {
       throw TypeError(`"dir" input may not be empty`);
     }
-    this.dir = `${dir}/Qt`;
+    this.dir = path.join(dir, "Qt");
 
     this.modules = Inputs.getStringArrayInput("modules");
 
@@ -450,7 +452,7 @@ const run = async (): Promise<void> => {
 
   // Set environment variables/outputs for tools
   if (inputs.tools.length && inputs.setEnv) {
-    core.exportVariable("IQTA_TOOLS", nativePath(`${inputs.dir}/Tools`));
+    core.exportVariable("IQTA_TOOLS", nativePath(path.join(inputs.dir, "Tools")));
   }
   // Set environment variables/outputs for binaries
   if (inputs.isInstallQtBinaries) {
@@ -461,19 +463,19 @@ const run = async (): Promise<void> => {
     // Set env variables
     if (inputs.setEnv) {
       if (process.platform === "linux") {
-        setOrAppendEnvVar("LD_LIBRARY_PATH", nativePath(`${qtPath}/lib`));
+        setOrAppendEnvVar("LD_LIBRARY_PATH", nativePath(path.join(qtPath, "lib")));
       }
       if (process.platform !== "win32") {
-        setOrAppendEnvVar("PKG_CONFIG_PATH", nativePath(`${qtPath}/lib/pkgconfig`));
+        setOrAppendEnvVar("PKG_CONFIG_PATH", nativePath(path.join(qtPath, "lib", "pkgconfig")));
       }
       // If less than qt6, set Qt5_DIR variable
       if (compareVersions(inputs.version, "<", "6.0.0")) {
-        core.exportVariable("Qt5_DIR", nativePath(`${qtPath}/lib/cmake`));
+        core.exportVariable("Qt5_DIR", nativePath(path.join(qtPath, "lib", "cmake")));
       }
       core.exportVariable("QT_ROOT_DIR", qtPath);
-      core.exportVariable("QT_PLUGIN_PATH", nativePath(`${qtPath}/plugins`));
-      core.exportVariable("QML2_IMPORT_PATH", nativePath(`${qtPath}/qml`));
-      core.addPath(nativePath(`${qtPath}/bin`));
+      core.exportVariable("QT_PLUGIN_PATH", nativePath(path.join(qtPath, "plugins")));
+      core.exportVariable("QML2_IMPORT_PATH", nativePath(path.join(qtPath, "qml")));
+      core.addPath(nativePath(path.join(qtPath, "bin")));
     }
   }
 };