fix: Read buid.target cargo config (#659)

fixes #653

.changes/read-build-target-config.md

@@ -0,0 +1,5 @@
+---
+action: 'patch'
+---
+
+The action now reads `build.target` from `.cargo/config` toml to get the correct `target` directory.

src/types.d.ts

@@ -69,3 +69,10 @@ export interface TauriConfig {
     };
   };
 }
+
+export interface CargoConfig {
+  build?: {
+    target?: string;
+    'target-dir'?: string;
+  };
+}

src/utils.ts

@@ -7,7 +7,13 @@ import { globbySync } from 'globby';
 
 import { getConfig, mergePlatformConfig, mergeUserConfig } from './config';
 
-import type { CargoManifest, Info, TargetInfo, TargetPlatform } from './types';
+import type {
+  CargoConfig,
+  CargoManifest,
+  Info,
+  TargetInfo,
+  TargetPlatform,
+} from './types';
 
 /*** constants ***/
 export const extensions = [
@@ -108,30 +114,60 @@ export function getWorkspaceDir(dir: string): string | null {
 }
 
 export function getTargetDir(crateDir: string): string {
+  // The default path if no configs are set.
   const def = join(crateDir, 'target');
-  if ('CARGO_TARGET_DIR' in process.env) {
-    return process.env.CARGO_TARGET_DIR ?? def;
-  }
+
+  // This will hold the path of current iteration
   let dir = crateDir;
+
+  // hold on to target-dir cargo config while we search for build.target
+  let targetDir;
+  // same for build.target
+  let targetDirExt;
+
+  // The env var takes precedence over config files.
+  if (process.env.CARGO_TARGET_DIR) {
+    targetDir = process.env.CARGO_TARGET_DIR ?? def;
+  }
+
   while (dir.length && dir[dir.length - 1] !== sep) {
     let cargoConfigPath = join(dir, '.cargo/config');
     if (!existsSync(cargoConfigPath)) {
       cargoConfigPath = join(dir, '.cargo/config.toml');
     }
     if (existsSync(cargoConfigPath)) {
-      const cargoConfig = parseToml(readFileSync(cargoConfigPath).toString());
-      // @ts-ignore
-      if (cargoConfig.build?.['target-dir']) {
-        // @ts-ignore
+      const cargoConfig = parseToml(
+        readFileSync(cargoConfigPath).toString(),
+      ) as CargoConfig;
+
+      if (!targetDir && cargoConfig.build?.['target-dir']) {
         const t = cargoConfig.build['target-dir'];
-        if (path.isAbsolute(t)) return t;
-        return normalize(join(dir, t));
+        if (path.isAbsolute(t)) {
+          targetDir = t;
+        } else {
+          targetDir = normalize(join(dir, t));
+        }
+      }
+
+      // Even if build.target is the same as the default target it will change the output dir.
+      // Just like tauri we only support a single string, not an array (bug?).
+      if (!targetDirExt && typeof cargoConfig.build?.target === 'string') {
+        targetDirExt = cargoConfig.build.target;
       }
     }
 
+    // If we got both we don't need to keep going
+    if (targetDir && targetDirExt) break;
+
+    // Prepare the path for the next iteration
     dir = normalize(join(dir, '..'));
   }
-  return def;
+
+  if (targetDir) {
+    return normalize(join(targetDir, targetDirExt ?? ''));
+  }
+
+  return normalize(join(def, targetDirExt ?? ''));
 }
 
 export function getCargoManifest(dir: string): CargoManifest {