add -v commandline option to improve error reporting, patch by Daniel

2008-03-23  Juerg Billeter  <j@bitron.ch>

	* vala/valareport.vala, vala/valasourcefile.vala,
	  compiler/valacompiler.vala: add -v commandline option to improve
	  error reporting, patch by Daniel Silverstone, fixes bug 522511

svn path=/trunk/; revision=1156

4 files changed, 100 insertions, 1 deletions

diff --git a/ChangeLog b/ChangeLog
index 32a4a868a..8a4d52d52 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,11 @@
 2008-03-23  Jürg Billeter  <j@bitron.ch>
 
+	* vala/valareport.vala, vala/valasourcefile.vala,
+	  compiler/valacompiler.vala: add -v commandline option to improve
+	  error reporting, patch by Daniel Silverstone, fixes bug 522511
+
+2008-03-23  Jürg Billeter  <j@bitron.ch>
+
 	* vapi/packages/json-glib-1.0/: add metadata to fix some memory
 	  leaks and out parameters, fixes bug 523889
 
diff --git a/compiler/valacompiler.vala b/compiler/valacompiler.vala
index 8d0b7c807..32e873d93 100644
--- a/compiler/valacompiler.vala
+++ b/compiler/valacompiler.vala
@@ -43,6 +43,7 @@ class Vala.Compiler : Object {
 	static bool disable_assert;
 	static bool disable_checking;
 	static bool non_null;
+	static bool verbose;
 	static string cc_command;
 	[NoArrayLength]
 	static string[] cc_options;
@@ -73,6 +74,7 @@ class Vala.Compiler : Object {
 		{ "Xcc", 'X', 0, OptionArg.STRING_ARRAY, out cc_options, "Pass OPTION to the C compiler", "OPTION..." },
 		{ "save-temps", 0, 0, OptionArg.NONE, out save_temps, "Keep temporary files", null },
 		{ "quiet", 'q', 0, OptionArg.NONE, ref quiet_mode, "Do not print messages to the console", null },
+		{ "verbose", 'v', 0, OptionArg.NONE, ref verbose, "Include the source line text when reporting errors or warnings." },
 		{ "", 0, 0, OptionArg.FILENAME_ARRAY, out sources, null, "FILE..." },
 		{ null }
 	};
@@ -143,6 +145,7 @@ class Vala.Compiler : Object {
 		context.assert = !disable_assert;
 		context.checking = !disable_checking;
 		context.non_null = non_null;
+		Report.set_verbose_errors (verbose);
 
 		context.ccode_only = ccode_only;
 		context.compile_only = compile_only;
diff --git a/vala/valareport.vala b/vala/valareport.vala
index f614ef929..d81940889 100644
--- a/vala/valareport.vala
+++ b/vala/valareport.vala
@@ -28,8 +28,17 @@ using GLib;
 public static class Vala.Report {
 	private static int warnings;
 	private static int errors;
+
+	private static bool verbose_errors;
 	
 	/**
+	 * Set the error verbosity.
+	 */
+	public static void set_verbose_errors (bool verbose) {
+		verbose_errors = verbose;
+	}
+
+	/**
 	 * Returns the total number of warnings reported.
 	 */
 	public static int get_warnings () {
@@ -44,6 +53,44 @@ public static class Vala.Report {
 	}
 
 	/**
+	 * Pretty-print the actual line of offending code if possible.
+	 */
+	private static void report_source (SourceReference! source) {
+		if (source.first_line != source.last_line) {
+			// FIXME Cannot report multi-line issues currently
+			return;
+		}
+
+		string offending_line = source.file.get_source_line (source.first_line);
+
+		if (offending_line != null) {
+			stderr.printf ("%s\n", offending_line);
+			int idx;
+			
+			/* We loop in this manner so that we don't fall over on differing
+			 * tab widths. This means we get the ^s in the right places.
+			 */
+			for (idx = 1; idx < source.first_column; ++idx) {
+				if (offending_line[idx - 1] == '\t') {
+					stderr.printf ("\t");
+				} else {
+					stderr.printf (" ");
+				}
+			}
+
+			for (idx = source.first_column; idx <= source.last_column; ++idx) {
+				if (offending_line[idx - 1] == '\t') {
+					stderr.printf ("\t");
+				} else {
+					stderr.printf ("^");
+				}
+			}
+
+			stderr.printf ("\n");
+		}
+	}
+
+	/**
 	 * Reports the specified message as warning.
 	 *
 	 * @param source  reference to source code
@@ -55,6 +102,9 @@ public static class Vala.Report {
 			stderr.printf ("warning: %s\n", message);
 		} else {
 			stderr.printf ("%s: warning: %s\n", source.to_string (), message);
+			if (verbose_errors) {
+				report_source (source);
+			}
 		}
 	}
 	
@@ -70,6 +120,9 @@ public static class Vala.Report {
 			stderr.printf ("error: %s\n", message);
 		} else {
 			stderr.printf ("%s: error: %s\n", source.to_string (), message);
+			if (verbose_errors) {
+				report_source (source);
+			}
 		}
 	}
 }
diff --git a/vala/valasourcefile.vala b/vala/valasourcefile.vala
index 8e4d82047..db955a69f 100644
--- a/vala/valasourcefile.vala
+++ b/vala/valasourcefile.vala
@@ -84,7 +84,9 @@ public class Vala.SourceFile : Object {
 	
 	private Gee.List<weak SourceFile> header_internal_full_dependencies = new ArrayList<weak SourceFile> ();
 	private Gee.List<weak SourceFile> header_internal_dependencies = new ArrayList<weak SourceFile> ();
-	
+
+	private Gee.ArrayList<string> source_array = null;
+
 	/**
 	 * Creates a new source file.
 	 *
@@ -359,6 +361,41 @@ public class Vala.SourceFile : Object {
 	public Collection<weak SourceFile> get_header_internal_dependencies () {
 		return new ReadOnlyCollection<weak SourceFile> (header_internal_dependencies);
 	}
+
+	/**
+	 * Returns the requested line from this file, loading it if needed.
+	 *
+	 * @param lineno 1-based line number
+	 * @return       the specified source line
+	 */
+	public string get_source_line (int lineno) {
+		if (source_array == null) {
+			read_source_file ();
+		}
+		if (lineno < 1 || lineno > source_array.size) {
+			return null;
+		}
+		return source_array.get (lineno - 1);
+	}
+
+	/**
+	 * Parses the input file into ::source_array.
+	 */
+	private void read_source_file () {
+		string cont;
+		source_array = new Gee.ArrayList<string> ();
+		try {
+			FileUtils.get_contents (filename, out cont);
+		} catch (FileError fe) {
+			return;
+		}
+		string[] lines = cont.split ("\n", 0);
+		uint idx;
+		for (idx = 0; lines[idx] != null; ++idx) {
+			source_array.add (lines[idx]);
+		}
+	}
+
 }
 
 public enum Vala.SourceFileDependencyType {