match erlang keywords more carefully

Use word boundaries in some regex matching to avoid recognizing words that
begin with keywords as keywords themselves, for example avoid recognizing a
function named catcher as the catch keyword. Add a regression test for this
problem.

3 files changed, 29 insertions, 7 deletions

diff --git a/lib/tools/emacs/erlang.el b/lib/tools/emacs/erlang.el
index f007f780eb..27397a52fd 100644
--- a/lib/tools/emacs/erlang.el
+++ b/lib/tools/emacs/erlang.el
@@ -2570,9 +2570,9 @@ Value is list (stack token-start token-type in-what)."
 		 (erlang-pop stack))
 	       (if (and stack (memq (car (car stack)) '(icr begin fun try)))
 		   (erlang-pop stack))))
-	    ((looking-at "catch.*of")
+	    ((looking-at "catch\\b.*of")
 	     t)
-	    ((looking-at "catch\\s *\\($\\|%\\|.*->\\)")
+	    ((looking-at "catch\\b\\s *\\($\\|%\\|.*->\\)")
 	     ;; Must pop top icr layer, `catch' in try/catch
 	     ;;will push a new layer next.
 	     (progn
@@ -2620,9 +2620,9 @@ Value is list (stack token-start token-type in-what)."
 	    ;;((looking-at "when\\s *\\($\\|%\\)")
 	    ((looking-at "when[^_a-zA-Z0-9]")
 	     (erlang-push (list 'when token (current-column)) stack))
-	    ((looking-at "catch.*of")
+	    ((looking-at "catch\\b.*of")
 	     t)
-	    ((looking-at "catch\\s *\\($\\|%\\|.*->\\)")
+	    ((looking-at "catch\\b\\s *\\($\\|%\\|.*->\\)")
 	     (erlang-push (list 'icr token (current-column)) stack))
 	    ;;(erlang-push (list '-> token (current-column)) stack))
 	    ;;((looking-at "^of$") 
@@ -2913,7 +2913,7 @@ Return nil if inside string, t if in a comment."
 			(if stack
 			    (erlang-caddr (car stack))
 			  0))
-		       ((looking-at "catch\\($\\|[^_a-zA-Z0-9]\\)")
+		       ((looking-at "catch\\b\\($\\|[^_a-zA-Z0-9]\\)")
 			;; Are we in a try
 			(let ((start (if (eq (car stack-top) '->)
 					 (car (cdr stack))
@@ -3124,12 +3124,12 @@ This assumes that the preceding expression is either simple
 (defun erlang-at-keyword ()
   "Are we looking at an Erlang keyword which will increase indentation?"
   (looking-at (concat "\\(when\\|if\\|fun\\|case\\|begin\\|"
-		      "of\\|receive\\|after\\|catch\\|try\\)[^_a-zA-Z0-9]")))
+		      "of\\|receive\\|after\\|catch\\|try\\)\\b")))
 
 (defun erlang-at-operator ()
   "Are we looking at an Erlang operator?"
   (looking-at
-   "\\(bnot\\|div\\|mod\\|band\\|bor\\|bxor\\|bsl\\|bsr\\)[^_a-zA-Z0-9]"))
+   "\\(bnot\\|div\\|mod\\|band\\|bor\\|bxor\\|bsl\\|bsr\\)\\b"))
 
 (defun erlang-comment-indent ()
   "Compute Erlang comment indentation.
diff --git a/lib/tools/emacs/test.erl.indented b/lib/tools/emacs/test.erl.indented
index 0dc1b47f0d..1c1086ca58 100644
--- a/lib/tools/emacs/test.erl.indented
+++ b/lib/tools/emacs/test.erl.indented
@@ -749,3 +749,14 @@ commas_first() ->
 %% this used to result in a scan-sexp error
 [{
  }].
+
+%% this used to result in 2x the correct indentation within the function
+%% body, due to the function name being mistaken for a keyword
+catcher(N) ->
+    try generate_exception(N) of
+	Val -> {N, normal, Val}
+    catch
+	throw:X -> {N, caught, thrown, X};
+	exit:X -> {N, caught, exited, X};
+	error:X -> {N, caught, error, X}
+    end.
diff --git a/lib/tools/emacs/test.erl.orig b/lib/tools/emacs/test.erl.orig
index c7d2dc4ce5..a9d09000d2 100644
--- a/lib/tools/emacs/test.erl.orig
+++ b/lib/tools/emacs/test.erl.orig
@@ -749,3 +749,14 @@ commas_first() ->
 %% this used to result in a scan-sexp error
 [{
 }].
+
+%% this used to result in 2x the correct indentation within the function
+%% body, due to the function name being mistaken for a keyword
+catcher(N) ->
+try generate_exception(N) of
+Val -> {N, normal, Val}
+catch
+throw:X -> {N, caught, thrown, X};
+exit:X -> {N, caught, exited, X};
+error:X -> {N, caught, error, X}
+end.