feat: handle install command errors

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+- better error messages for `myrc install`
+
 ## [0.1.0] - 2024-01-24
 
 ### Added
@@ -15,3 +17,6 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - experimental CLI output
 - symlinking functionality
 - selected [SDL](https://sdlang.org/) format for install file (`install.sdl`)
+
+[unreleased]: https://github.com/kucaahbe/myrc.d/compare/v0.1.0...HEAD
+[0.1.0]: https://github.com/kucaahbe/myrc.d/releases/tag/v0.1.0

source/cli.d

@@ -51,11 +51,19 @@ void cli_install(ref Config app_config)
 			output ~= " -> ";
 			output ~= symlink.source.absolute;
 		} else {
-			string backup = symlink.link();
-			output ~= " -> ";
-			output ~= symlink.source.absolute;
-			if (backup)
-				output ~= " (backup: " ~ backup ~ ")";
+			import std.file: FileException;
+			try
+			{
+				string backup = symlink.link();
+				output ~= " -> ";
+				output ~= symlink.source.absolute;
+				if (backup)
+					output ~= " (backup: " ~ backup ~ ")";
+			}
+			catch (FileException e)
+			{
+				output ~= " # error: " ~ e.msg;
+			}
 		}
 		output ~= "\n";
 	}

source/path.d

@@ -1,5 +1,5 @@
 import std.array;
-import std.path: expandTilde, absolutePath, asNormalizedPath;
+import std.path: expandTilde, absolutePath, asNormalizedPath, dirName;
 import std.file: exists, isDir, isSymlink;
 
 /** represent path in a file system */
@@ -69,6 +69,24 @@ struct Path
 		assert(path.exists);
 	}
 
+	/** Returns: [Path] representing _parent folder
+	 */
+	Path parent() inout
+	{
+		return Path(absolute.dirName);
+	}
+
+	/// returns parent folder as [Path]
+	unittest
+	{
+		import std.file;
+
+		immutable auto cwd = getcwd();
+
+		immutable auto path = Path(".test/app/source");
+		assert(path.parent.absolute == cwd ~ '/' ~ ".test/app");
+	}
+
 	/** Returns: true if [Path] is a directory in a file system */
 	bool isDir() inout
 	{

source/symlink.d

@@ -79,6 +79,17 @@ struct Symlink {
 	 */
 	string link()
 	{
+		if (!source.exists)
+			throw new FileException(source.absolute, "file or directory does not exist");
+
+		auto parentDir = destination.parent;
+
+		if (!parentDir.exists)
+			throw new FileException(parentDir.absolute, "directory does not exist");
+
+		if (!parentDir.isDir)
+			throw new FileException(parentDir.absolute, "not a directory");
+
 		string backupPath;
 
 		if (destination.exists)
@@ -94,15 +105,16 @@ struct Symlink {
 	{
 		import std.file;
 		import std.path;
+		import test_file;
 
 		if (".test".exists) ".test".rmdirRecurse;
 		scope(exit) if (".test".exists) ".test".rmdirRecurse;
 
 		auto srcPath = ".test/app/source";
 		auto destPath = ".test/home/destination";
 
-		srcPath.dirName.mkdirRecurse;
-		destPath.dirName.mkdirRecurse;
+		TestFile(srcPath, "content").create;
+		TestFile(destPath).create;
 
 		auto link = Symlink(srcPath, destPath);
 		link.link();
@@ -140,6 +152,93 @@ struct Symlink {
 		assert(backup == destPathBackup, backup ~ "!=" ~ destPathBackup);
 	}
 
+	/** **fail case**: destination does not exist
+		* (raises [FileException] with corresponding message)
+		*/
+	unittest
+	{
+		import std.file;
+		import std.path;
+		import test_file;
+		import std.exception: collectExceptionMsg;
+
+		if (".test".exists) ".test".rmdirRecurse;
+		scope(exit) if (".test".exists) ".test".rmdirRecurse;
+
+		immutable auto cwd = getcwd();
+		auto srcPath = ".test/app/source";
+		auto destPath = ".test/home/destination";
+
+		TestFile(srcPath, "content").create;
+		// only create .test/
+		TestFile(destPath.dirName).create;
+		assert(destPath.dirName.dirName.isDir);
+
+		auto link = Symlink(srcPath, destPath);
+
+		immutable auto exceptionMsg = collectExceptionMsg!FileException(link.link);
+		immutable auto expectedExceptionMsg = cwd ~ "/.test/home" ~ ": directory does not exist";
+
+		assert(exceptionMsg == expectedExceptionMsg, exceptionMsg ~ " != " ~ expectedExceptionMsg);
+	}
+
+	/** **fail case**: destination is not a directory
+	 * (raises [FileException] with corresponding message)
+	 */
+	unittest
+	{
+		import std.file;
+		import std.path;
+		import test_file;
+		import std.exception: collectExceptionMsg;
+
+		if (".test".exists) ".test".rmdirRecurse;
+		scope(exit) if (".test".exists) ".test".rmdirRecurse;
+
+		auto srcPath = ".test/app/source";
+		auto destPath = ".test/home/destination";
+		immutable auto cwd = getcwd();
+
+		TestFile(srcPath, "src content").create;
+		// destination directory is a file
+		TestFile(destPath.dirName, "dest content").create;
+
+		auto link = Symlink(srcPath, destPath);
+
+		immutable auto exceptionMsg = collectExceptionMsg!FileException(link.link);
+		immutable auto expectedExceptionMsg = cwd ~ '/' ~ destPath.dirName ~ ": not a directory";
+
+		assert(exceptionMsg == expectedExceptionMsg, exceptionMsg ~ " != " ~ expectedExceptionMsg);
+	}
+
+	/** **fail case**: source does not exist
+	 * (raises [FileException] with corresponding message)
+	 */
+	unittest
+	{
+		import std.file;
+		import std.path;
+		import test_file;
+		import std.exception: collectExceptionMsg;
+
+		if (".test".exists) ".test".rmdirRecurse;
+		scope(exit) if (".test".exists) ".test".rmdirRecurse;
+
+		auto srcPath = ".test/app/source";
+		auto destPath = ".test/home/destination";
+		immutable auto cwd = getcwd();
+
+		TestFile(destPath).create;
+		assert(destPath.dirName.isDir);
+
+		auto link = Symlink(srcPath, destPath);
+
+		immutable auto exceptionMsg = collectExceptionMsg!FileException(link.link);
+		immutable auto expectedExceptionMsg = cwd ~ "/.test/app/source" ~ ": file or directory does not exist";
+
+		assert(exceptionMsg == expectedExceptionMsg, exceptionMsg ~ " != " ~ expectedExceptionMsg);
+	}
+
 	/** Returns: _actual [Path] of the destination */
 	Path actual() const
 	{