stgit.el: Add command for showing diff for a range of patches

[stgit] / contrib / stgit.el

diff --git a/contrib/stgit.el b/contrib/stgit.el
index f617e6d..73c8e4b 100644 (file)
--- a/contrib/stgit.el
+++ b/contrib/stgit.el
@@ -940,6 +940,7 @@ file for (applied) copies and renames."
             ("c" .        stgit-diff-combined)
             ("m" .        stgit-find-file-merge)
             ("o" .        stgit-diff-ours)
+            ("r" .        stgit-diff-range)
             ("t" .        stgit-diff-theirs)))
     (suppress-keymap toggle-map)
     (mapc (lambda (arg) (define-key toggle-map (car arg) (cdr arg)))
@@ -1077,6 +1078,8 @@ file for (applied) copies and renames."
         "-"
         ["Show diff" stgit-diff
          :active (get-text-property (point) 'entry-type)]
+        ["Show diff for range of applied patches" stgit-diff-range
+         :active (= (length stgit-marked-patches) 1)]
         ("Merge"
          :active (stgit-git-index-unmerged-p)
          ["Combined diff" stgit-diff-combined
@@ -1191,6 +1194,7 @@ Display commands:
 
 Commands for diffs:
 \\[stgit-diff] Show diff of patch or file
+\\[stgit-diff-range]   Show diff for range of patches
 \\[stgit-diff-base]    Show diff against the merge base
 \\[stgit-diff-ours]    Show diff against our branch
 \\[stgit-diff-theirs]  Show diff against their branch
@@ -1718,16 +1722,17 @@ If PATCHSYM is a keyword, returns PATCHSYM unmodified."
        (error "Cannot find commit id for %s" patchsym))
       (match-string 1 result))))
 
+(defun stgit-whitespace-diff-arg (arg)
+  (when (numberp arg)
+    (cond ((> arg 4) "--ignore-all-space")
+          ((> arg 1) "--ignore-space-change"))))
+
 (defun stgit-show-patch (unmerged-stage ignore-whitespace)
   "Show the patch on the current line.
 
 UNMERGED-STAGE is the argument to `git-diff' that that selects
 which stage to diff against in the case of unmerged files."
-  (let ((space-arg (when (numberp ignore-whitespace)
-                     (cond ((> ignore-whitespace 4)
-                            "--ignore-all-space")
-                           ((> ignore-whitespace 1)
-                            "--ignore-space-change"))))
+  (let ((space-arg (stgit-whitespace-diff-arg ignore-whitespace))
         (patch-name (stgit-patch-name-at-point t)))
     (stgit-capture-output "*StGit patch*"
       (case (get-text-property (point) 'entry-type)
@@ -1803,6 +1808,35 @@ greater than four (e.g., \\[universal-argument] \
                    "--cc"
                    "show a combined diff")
 
+(defun stgit-diff-range (&optional ignore-whitespace)
+  "Show diff for the range of patches between point and the marked patch.
+
+With a prefix argument, ignore whitespace. With a prefix argument
+greater than four (e.g., \\[universal-argument] \
+\\[universal-argument] \\[stgit-diff-range]), ignore all whitespace."
+  (interactive "p")
+  (stgit-assert-mode)
+  (unless (= (length stgit-marked-patches) 1)
+    (error "Need exactly one patch marked"))
+  (let* ((patches (stgit-sort-patches (cons (stgit-patch-name-at-point t t)
+                                            stgit-marked-patches)
+                                      t))
+         (first-patch (car patches))
+         (second-patch (if (cdr patches) (cadr patches) first-patch))
+         (whitespace-arg (stgit-whitespace-diff-arg ignore-whitespace))
+         (applied (stgit-applied-patchsyms t)))
+    (unless (and (memq first-patch applied) (memq second-patch applied))
+      (error "Can only show diff range for applied patches"))
+    (stgit-capture-output (format "*StGit diff %s..%s*"
+                                  first-patch second-patch)
+      (apply 'stgit-run-git (append '("diff" "--patch-with-stat")
+                                    (and whitespace-arg (list whitespace-arg))
+                                    (list (format "%s^" (stgit-id first-patch))
+                                          (stgit-id second-patch))))
+      (with-current-buffer standard-output
+        (goto-char (point-min))
+        (diff-mode)))))
+
 (defun stgit-move-change-to-index (file &optional force)
   "Copies the work tree state of FILE to index, using git add or git rm.
 
@@ -2021,11 +2055,12 @@ patches."
                 (t (setq result :bottom)))))
       result)))
 
-(defun stgit-sort-patches (patchsyms)
+(defun stgit-sort-patches (patchsyms &optional allow-duplicates)
   "Returns the list of patches in PATCHSYMS sorted according to
 their position in the patch series, bottommost first.
 
-PATCHSYMS must not contain duplicate entries."
+PATCHSYMS must not contain duplicate entries, unless
+ALLOW-DUPLICATES is not nil."
   (let (sorted-patchsyms
         (series (with-output-to-string
                   (with-current-buffer standard-output
@@ -2038,8 +2073,9 @@ PATCHSYMS must not contain duplicate entries."
       (setq start (match-end 0)))
     (setq sorted-patchsyms (nreverse sorted-patchsyms))
 
-    (unless (= (length patchsyms) (length sorted-patchsyms))
-      (error "Internal error"))
+    (unless allow-duplicates
+      (unless (= (length patchsyms) (length sorted-patchsyms))
+        (error "Internal error")))
 
     sorted-patchsyms))