From 9eaf461db3d725329fd72f41c93d3e765e7725e4 Mon Sep 17 00:00:00 2001
From: Dan Aloni <alonid@gmail.com>
Date: Tue, 29 Sep 2015 10:52:23 +0300
Subject: [PATCH 1/3] haskell-load: add haskell-goto-first-error

---
 haskell-load.el | 6 ++++++
 haskell.el      | 1 +
 2 files changed, 7 insertions(+)

diff --git a/haskell-load.el b/haskell-load.el
index dc2647b64..4bd622d21 100644
--- a/haskell-load.el
+++ b/haskell-load.el
@@ -346,6 +346,12 @@ correspondingly-named overlay properties of OVL."
 	(t
 	 (message "No further notes from Haskell compiler."))))
 
+(defun haskell-goto-first-error ()
+  (interactive)
+  (haskell-goto-error-overlay
+   (first-overlay-in-if 'haskell-check-overlay-p
+                        (buffer-end 0) (buffer-end 1))))
+
 (defun haskell-goto-prev-error ()
   (interactive)
   (haskell-goto-error-overlay
diff --git a/haskell.el b/haskell.el
index d8d424dfc..cbf5c816f 100644
--- a/haskell.el
+++ b/haskell.el
@@ -54,6 +54,7 @@
     (define-key map [?\C-c ?\C-z] 'haskell-interactive-switch)
     (define-key map (kbd "M-n") 'haskell-goto-next-error)
     (define-key map (kbd "M-p") 'haskell-goto-prev-error)
+    (define-key map (kbd "C-c M-p") 'haskell-goto-first-error)
     map)
   "Keymap for using haskell-interactive-mode.")
 

From e6f3ca5380511ae21207ce41eab0e905562d4cb9 Mon Sep 17 00:00:00 2001
From: Daniel Bergey <bergey@teallabs.org>
Date: Thu, 21 Jan 2016 22:22:47 -0500
Subject: [PATCH 2/3] add tests for goto-error functions

- haskell-goto-next-error
- haskell-goto-prev-error
- haskell-goto-first-error
---
 tests/haskell-load-tests.el | 85 +++++++++++++++++++++++++++++++++++++
 1 file changed, 85 insertions(+)
 create mode 100644 tests/haskell-load-tests.el

diff --git a/tests/haskell-load-tests.el b/tests/haskell-load-tests.el
new file mode 100644
index 000000000..227f2e180
--- /dev/null
+++ b/tests/haskell-load-tests.el
@@ -0,0 +1,85 @@
+;;; haskell-load-tests.el
+
+;;; Code:
+
+(require 'ert)
+(require 'haskell-test-utils)
+
+(require 'haskell-load)
+
+(defun insert-errors ()
+  (insert "import Control.Applicativ\nimport Data.Mayb\nimport Data.String")
+  (goto-char 1)
+  (let ((applicativ (progn
+                      (search-forward "Control.Applicativ")
+                      (make-overlay (match-beginning 0) (match-end 0)))))
+    (overlay-put applicativ 'haskell-check t)
+    (overlay-put applicativ 'haskell-msg-type 'error)
+    (overlay-put applicativ 'haskell-msg "Could not find module ‘Control.Applicativ’\n    Perhaps you meant Control.Applicative (from base-4.8.1.0)\n    Use -v to see a list of the files searched for."))
+  (let ((mayb (progn
+                (search-forward "Data.Mayb")
+                (make-overlay (match-beginning 0) (match-end 0)))))
+    (overlay-put mayb 'haskell-check t)
+    (overlay-put mayb 'haskell-msg-type 'error)
+    (overlay-put mayb 'haskell-msg "Could not find module ‘Data.Mayb’\n    Perhaps you meant\n      Data.Maybe (from base-4.8.1.0)\n      Data.Map (from containers-0.5.6.2@conta_LKCPrTJwOTOLk4OU37YmeN)\n    Use -v to see a list of the files searched for."))
+  (goto-char 1))
+
+(ert-deftest goto-first-error-before ()
+  (with-temp-switch-to-buffer
+   (insert-errors)
+   (haskell-goto-first-error)
+   (should (looking-at-p "Control.Applicativ"))))
+
+(ert-deftest goto-first-error-after ()
+  (with-temp-switch-to-buffer
+   (insert-errors)
+   (search-forward "Data.String")
+   (haskell-goto-first-error)
+   (should (looking-at-p "Control.Applicativ"))))
+
+(ert-deftest goto-first-error-between ()
+  (with-temp-switch-to-buffer
+   (insert-errors)
+   (search-forward "import Data.Mayb")
+   (haskell-goto-first-error)
+   (should (looking-at-p "Control.Applicativ"))))
+
+(ert-deftest goto-next-error-before ()
+  (with-temp-switch-to-buffer
+   (insert-errors)
+   (haskell-goto-next-error)
+   (should (looking-at-p "Control.Applicativ"))))
+
+(ert-deftest goto-next-error-between ()
+  (with-temp-switch-to-buffer
+   (insert-errors)
+   (search-forward "import" nil nil 2)
+   (haskell-goto-next-error)
+   (should (looking-at-p "Data.Mayb"))))
+
+(ert-deftest goto-next-error-after ()
+  (with-temp-switch-to-buffer
+   (insert-errors)
+   (search-forward "import" nil nil 3)
+   (haskell-goto-next-error)
+   (should (looking-at-p " Data.String"))))
+
+(ert-deftest goto-prev-error-before ()
+  (with-temp-switch-to-buffer
+   (insert-errors)
+   (haskell-goto-prev-error)
+   (should (looking-at-p "import Control.Applicativ"))))
+
+(ert-deftest goto-prev-error-between ()
+  (with-temp-switch-to-buffer
+   (insert-errors)
+   (search-forward "import" nil nil 2)
+   (haskell-goto-prev-error)
+   (should (looking-at-p "Control.Applicativ"))))
+
+(ert-deftest goto-prev-error-after ()
+  (with-temp-switch-to-buffer
+   (insert-errors)
+   (search-forward "import Data.String")
+   (haskell-goto-prev-error)
+   (should (looking-at-p "Data.Mayb"))))

From 788a70ce4cd56104ed490e028487e56c57de25d1 Mon Sep 17 00:00:00 2001
From: Daniel Bergey <bergey@teallabs.org>
Date: Thu, 21 Jan 2016 22:33:38 -0500
Subject: [PATCH 3/3] manual: mention goto-error functions

---
 doc/haskell-mode.texi | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/doc/haskell-mode.texi b/doc/haskell-mode.texi
index a76854fa2..f1a5fe814 100644
--- a/doc/haskell-mode.texi
+++ b/doc/haskell-mode.texi
@@ -730,6 +730,21 @@ associated with at most one GHCi session, so when you call
 no session associated yet, you're asked which GHCi session to create or
 associate with.
 
+@section Goto Error
+
+In a Haskell source buffer associated with a GHCi session, errors that
+prevent the file from loading are highlighted with
+@code{haskell-error-face}.  You can move between these error lines with
+
+@table @kbd
+@item M-n
+is bound to @code{haskell-goto-next-error}
+@item M-p
+is bound to @code{haskell-goto-prev-error}
+@item C-c M-p
+is bound to @code{haskell-goto-first-error}
+@end table
+
 @section Using GHCi-ng
 
 Put @code{:set +c} in your @code{.ghci} or run it in the REPL. Then use