Make occur handle multi-line matches cleanly with context.

http://lists.gnu.org/archive/html/emacs-devel/2010-03/msg01280.html

* replace.el (occur-accumulate-lines): Add optional arg `pt'.
(occur-engine): Add local variables `ret', `prev-after-lines',
`prev-lines'.  Use more arguments for `occur-context-lines'.
Set first elem of its returned list to `data', and the second elem
to `prev-after-lines'.  Don't print the separator line.
In the end, print remaining context after-lines.
(occur-context-lines): Add new arguments `begpt', `endpt',
`lines', `prev-lines', `prev-after-lines'.  Rewrite to combine
after-lines of the previous match with before-lines of the
current match and not overlap them.  Return a list with two
values: the output line and the list of context after-lines.

* search.texi (Other Repeating Search): Remove line that `occur'
can not handle multiline matches.

* occur-testsuite.el (occur-tests): Add tests for context lines.

2 files changed, 212 insertions, 1 deletions

diff --git a/test/ChangeLog b/test/ChangeLog
index ee69172241d..87847a43ada 100644
--- a/test/ChangeLog
+++ b/test/ChangeLog
@@ -1,3 +1,7 @@
+2010-03-30  Juri Linkov  <juri@jurta.org>
+
+        * occur-testsuite.el (occur-tests): Add tests for context lines.
+
 2010-03-23  Juri Linkov  <juri@jurta.org>
 
         * occur-testsuite.el: New file.
diff --git a/test/occur-testsuite.el b/test/occur-testsuite.el
index d817805dd67..a4756c49e2a 100644
--- a/test/occur-testsuite.el
+++ b/test/occur-testsuite.el
@@ -107,7 +107,214 @@ fx
        :fx
        :
 ")
-    )
+    ;; * Test non-overlapping context lines with matches at bob/eob.
+    ("x" 1 "\
+ax
+b
+c
+d
+ex
+f
+g
+hx
+" "\
+3 matches for \"x\" in buffer:  *temp*
+      1:ax
+       :b
+-------
+       :d
+      5:ex
+       :f
+-------
+       :g
+      8:hx
+")
+    ;; * Test non-overlapping context lines with matches not at bob/eob.
+    ("x" 1 "\
+a
+bx
+c
+d
+ex
+f
+" "\
+2 matches for \"x\" in buffer:  *temp*
+       :a
+      2:bx
+       :c
+-------
+       :d
+      5:ex
+       :f
+")
+    ;; * Test overlapping context lines with matches at bob/eob.
+    ("x" 2 "\
+ax
+bx
+c
+dx
+e
+f
+gx
+h
+i
+j
+kx
+" "\
+5 matches for \"x\" in buffer:  *temp*
+      1:ax
+      2:bx
+       :c
+      4:dx
+       :e
+       :f
+      7:gx
+       :h
+       :i
+       :j
+     11:kx
+")
+    ;; * Test overlapping context lines with matches not at bob/eob.
+    ("x" 2 "\
+a
+b
+cx
+d
+e
+f
+gx
+h
+i
+" "\
+2 matches for \"x\" in buffer:  *temp*
+       :a
+       :b
+      3:cx
+       :d
+       :e
+       :f
+      7:gx
+       :h
+       :i
+")
+    ;; * Test overlapping context lines with empty first and last line..
+    ("x" 2 "\
+
+b
+cx
+d
+e
+f
+gx
+h
+
+" "\
+2 matches for \"x\" in buffer:  *temp*
+       :
+       :b
+      3:cx
+       :d
+       :e
+       :f
+      7:gx
+       :h
+       :
+")
+    ;; * Test multi-line overlapping context lines.
+    ("x\n.x" 2 "\
+ax
+bx
+c
+d
+ex
+fx
+g
+h
+i
+jx
+kx
+" "\
+3 matches for \"x^J.x\" in buffer:  *temp*
+      1:ax
+       :bx
+       :c
+       :d
+      5:ex
+       :fx
+       :g
+       :h
+       :i
+     10:jx
+       :kx
+")
+    ;; * Test multi-line non-overlapping context lines.
+    ("x\n.x" 2 "\
+ax
+bx
+c
+d
+e
+f
+gx
+hx
+" "\
+2 matches for \"x^J.x\" in buffer:  *temp*
+      1:ax
+       :bx
+       :c
+       :d
+-------
+       :e
+       :f
+      7:gx
+       :hx
+")
+    ;; * Test non-overlapping negative (before-context) lines.
+    ("x" -2 "\
+a
+bx
+c
+d
+e
+fx
+g
+h
+ix
+" "\
+3 matches for \"x\" in buffer:  *temp*
+       :a
+      2:bx
+-------
+       :d
+       :e
+      6:fx
+-------
+       :g
+       :h
+      9:ix
+")
+    ;; * Test overlapping negative (before-context) lines.
+    ("x" -3 "\
+a
+bx
+c
+dx
+e
+f
+gx
+h
+" "\
+3 matches for \"x\" in buffer:  *temp*
+       :a
+      2:bx
+       :c
+      4:dx
+       :e
+       :f
+      7:gx
+")
+
+)
   "List of tests for `occur'.
 Each element has the format:
 \(REGEXP NLINES INPUT-BUFFER-STRING OUTPUT-BUFFER-STRING).")