Add "go to next/previous error" commands.

Inspired by SublimeClang.

Default.sublime-commands

@@ -84,5 +84,13 @@
     {
         "caption": "SublimeHaskell: Reinspect all",
         "command": "sublime_haskell_reinspect_all"
+    },
+    {
+        "caption": "SublimeHaskell: Go to next error",
+        "command": "sublime_haskell_next_error"
+    },
+    {
+        "caption": "SublimeHaskell: Go to previous error",
+        "command": "sublime_haskell_previous_error"
     }
 ]

Default.sublime-keymap

@@ -13,5 +13,16 @@
         "args": {"characters": "("},
         "keys": ["("],
         "context": [ { "key": "is_haskell_source" }, { "key": "auto_completion_popup" } ]
+    },
+    // Same keybindings as SublimeClang
+    {
+        "command": "sublime_haskell_next_error",
+        "keys": ["alt+d", "alt+e"],
+        "context": [ { "key": "is_haskell_source" } ]
+    },
+    {
+        "command": "sublime_haskell_previous_error",
+        "keys": ["alt+shift+d", "alt+shift+e"],
+        "context": [ { "key": "is_haskell_source" } ]
     }
 ]

ghcmod.py

@@ -4,7 +4,7 @@
 from threading import Thread
 
 from sublime_haskell_common import log, is_enabled_haskell_command, get_haskell_command_window_view_file_project, call_ghcmod_and_wait
-from parseoutput import parse_output_messages, show_output_result_text, format_output_messages, mark_messages_in_views, hide_output
+from parseoutput import parse_output_messages, show_output_result_text, format_output_messages, mark_messages_in_views, hide_output, set_global_error_messages
 
 
 def lint_as_hints(msgs):
@@ -118,6 +118,9 @@ def wait_ghcmod_and_parse(view, filename, msg, cmds_with_args, alter_messages_cb
         for p in parsed:
             parsed_messages.append((cmd, p))
 
+        # Set global error list
+        set_global_error_messages(parsed)
+
     if alter_messages_cb:
         alter_messages_cb(parsed_messages)
 

parseoutput.py

@@ -1,8 +1,10 @@
 import os
 import re
 import sublime
+import sublime_plugin
 import time
 from threading import Thread
+from collections import defaultdict
 
 from sublime_haskell_common import log, are_paths_equal, call_and_wait, get_setting_async
 
@@ -20,6 +22,12 @@
 result_file_regex = r'^(\S*?): line (\d+), column (\d+):$'
 
 
+# Global list of errors. Used e.g. for jumping to the next one.
+# Properly assigned being a defaultdict in clear_error_marks().
+# Structure: ERRORS[filename][m.line] = OutputMessage()
+ERRORS = {}
+
+
 def filename_of_path(p):
     """Returns everything after the last slash or backslash."""
     # Not using os.path here because we don't know/care here if
@@ -61,6 +69,22 @@ def find_region_in_view(self, view):
         return region
 
 
+def clear_error_marks():
+    global ERRORS
+
+    listdict = lambda: defaultdict(list)
+    ERRORS = defaultdict(listdict)
+
+
+def set_global_error_messages(messages):
+    global ERRORS
+
+    clear_error_marks()
+
+    for m in messages:
+        ERRORS[m.filename][m.line].append(m)
+
+
 def run_build_thread(view, cabal_project_dir, msg, cmd, on_done):
     run_chain_build_thread(view, cabal_project_dir, msg, [cmd], on_done)
 
@@ -133,6 +157,9 @@ def parse_output_messages_and_show(view, msg, base_dir, exit_code, stderr):
     # The unparseable part (for other errors)
     unparsable = output_regex.sub('', stderr).strip()
 
+    # Set global error list
+    set_global_error_messages(parsed_messages)
+
     # If we couldn't parse any messages, just show the stderr
     # Otherwise the parsed errors and the unparsable stderr remainder
     outputs = []
@@ -183,6 +210,50 @@ def mark_messages_in_views(errors):
 }
 
 
+# These next and previous commands were shamelessly copied
+# from the great SublimeClang plugin.
+
+class SublimeHaskellNextError(sublime_plugin.TextCommand):
+    def run(self, edit):
+        print "SublimeHaskellNextError"
+        v = self.view
+        fn = v.file_name().encode("utf-8")
+        line, column = v.rowcol(v.sel()[0].a)
+        gotoline = -1
+        if fn in ERRORS:
+            for errLine in ERRORS[fn]:
+                if errLine > line:
+                    gotoline = errLine
+                    break
+            # No next line: Wrap around if possible
+            if gotoline == -1 and len(ERRORS[fn]) > 0:
+                gotoline = ERRORS[fn].keys()[0]
+        if gotoline != -1:
+            v.window().open_file("%s:%d" % (fn, gotoline), sublime.ENCODED_POSITION)
+        else:
+            sublime.status_message("No more errors or warnings!")
+
+
+class SublimeHaskellPreviousError(sublime_plugin.TextCommand):
+    def run(self, edit):
+        v = self.view
+        fn = v.file_name().encode("utf-8")
+        line, column = v.rowcol(v.sel()[0].a)
+        gotoline = -1
+        if fn in ERRORS:
+            for errLine in ERRORS[fn]:
+                if errLine < line:
+                    gotoline = errLine
+            # No previous line: Wrap around if possible
+            if gotoline == -1 and len(ERRORS[fn]) > 0:
+                gotoline = ERRORS[fn].keys()[-1]
+        if gotoline != -1:
+            v.window().open_file("%s:%d" % (fn, gotoline), sublime.ENCODED_POSITION)
+        else:
+            sublime.status_message("No more errors or warnings!")
+
+
+
 def region_key(name):
     return 'subhs-{0}s'.format(name)