From 6fd4cd0ecd32e0d8246f3678ff21bdb8a1a80016 Mon Sep 17 00:00:00 2001
From: Luna <git@l4.pm>
Date: Fri, 9 Aug 2019 11:28:40 -0300
Subject: [PATCH] add better error messages for no cmd and unknown cmd

---
 src/lang.zig | 29 ++++++++++++++++++++---------
 1 file changed, 20 insertions(+), 9 deletions(-)

diff --git a/src/lang.zig b/src/lang.zig
index 92f651e..dc29439 100644
--- a/src/lang.zig
+++ b/src/lang.zig
@@ -135,6 +135,9 @@ pub const Lang = struct {
     allocator: *std.mem.Allocator,
     keywords: KeywordMap,
 
+    has_error: bool = false,
+    line: usize = 0,
+
     pub fn init(allocator: *std.mem.Allocator) Lang {
         return Lang{
             .allocator = allocator,
@@ -287,14 +290,20 @@ pub const Lang = struct {
         }
     }
 
+    fn doError(self: *Lang, comptime fmt: []const u8, args: ...) void {
+        std.debug.warn("error at line {}: ", self.line);
+        std.debug.warn(fmt, args);
+        std.debug.warn("\n");
+        self.has_error = true;
+    }
+
     pub fn parse(self: *Lang, data: []const u8) !CommandList {
         var splitted_it = std.mem.separate(data, ";");
         try self.fillKeywords();
         var cmds = CommandList.init(self.allocator);
-        var idx: usize = 0;
-        var has_error = false;
 
         while (splitted_it.next()) |stmt_orig| {
+            self.line += 1;
             var stmt = std.mem.trimRight(u8, stmt_orig, "\n");
             stmt = std.mem.trimLeft(u8, stmt, "\n");
 
@@ -305,7 +314,10 @@ pub const Lang = struct {
             var tok_it = std.mem.tokenize(stmt, " ");
 
             var cmd_opt = tok_it.next();
-            if (cmd_opt == null) return ParseError.NoCommandGiven;
+            if (cmd_opt == null) {
+                self.doError("No command given");
+                continue;
+            }
             var command = cmd_opt.?;
 
             var ctype_opt = self.getCommand(command);
@@ -313,8 +325,8 @@ pub const Lang = struct {
             if (ctype_opt) |ctype_val| {
                 ctype = ctype_val;
             } else {
-                std.debug.warn("Unknown command: '{}' ({})\n", command, command.len);
-                return ParseError.UnknownCommand;
+                self.doError("Unknown command '{}' ({})", command, command.len);
+                continue;
             }
 
             var args = ArgList.init(self.allocator);
@@ -328,15 +340,14 @@ pub const Lang = struct {
 
             cmd_ptr.* = Command{ .command = ctype, .args = args };
             self.validateCommand(cmd_ptr) catch |err| {
-                std.debug.warn("error at line {}: {}\n", idx, err);
-                has_error = true;
+                self.doError("Unknown command '{}' (length {})", command, command.len);
+                continue;
             };
 
             try cmds.append(cmd_ptr);
-            idx += 1;
         }
 
-        if (has_error) return ParseError.ParseFail;
+        if (self.has_error) return ParseError.ParseFail;
 
         return cmds;
     }