Re: skipping assignment and function statements; Interactive comments

[Peter Stephenson <p.w.stephenson@ntlworld.com>]

On Sat, 23 Aug 2008 00:15:31 -0400
"Rocky Bernstein" <rocky.bernstein@gmail.com> wrote:
> I just added a skip command to zshdb (and committed to github), but it
> seems that assignment statements and function definitions are not
> really skipped.

Yes, thanks, there's yet another infuriating special case of the sort
that makes me wish I'd picked an easier project.

That's the third change here; the stuff with intrap is because it
doesn't detect that it's already inside a trap (and hence should skip
debugging) until it gets into dotrapargs(), and in this case it seems
neater not to go to the trouble.  This will be even more sensible when I
get around to regenerating the line to be debugged at this point.

Index: Src/exec.c
===================================================================
RCS file: /cvsroot/zsh/zsh/Src/exec.c,v
retrieving revision 1.141
diff -u -r1.141 exec.c
--- Src/exec.c	22 Aug 2008 15:41:31 -0000	1.141
+++ Src/exec.c	25 Aug 2008 17:21:19 -0000
@@ -1068,7 +1068,7 @@
 		lineno = lnp1 - 1;
 	}
 
-	if (sigtrapped[SIGDEBUG] && isset(DEBUGBEFORECMD)) {
+	if (sigtrapped[SIGDEBUG] && isset(DEBUGBEFORECMD) && !intrap) {
 	    int oerrexit_opt = opts[ERREXIT];
 	    opts[ERREXIT] = 0;
 	    noerrexit = 1;
@@ -1086,11 +1086,12 @@
 	    donedebug = isset(ERREXIT) ? 2 : 1;
 	    opts[ERREXIT] = oerrexit_opt;
 	} else
-	    donedebug = 0;
+	    donedebug = intrap ? 1 : 0;
 
 	if (ltype & Z_SIMPLE) {
 	    next = state->pc + WC_LIST_SKIP(code);
-	    execsimple(state);
+	    if (donedebug != 2)
+		execsimple(state);
 	    state->pc = next;
 	    goto sublist_done;
 	}
Index: Test/C03traps.ztst
===================================================================
RCS file: /cvsroot/zsh/zsh/Test/C03traps.ztst,v
retrieving revision 1.14
diff -u -r1.14 C03traps.ztst
--- Test/C03traps.ztst	7 Aug 2008 16:25:16 -0000	1.14
+++ Test/C03traps.ztst	25 Aug 2008 17:21:19 -0000
@@ -415,6 +415,20 @@
 >3 three
 >5 five
 
+  # Assignments are a special case, since they use a simpler
+  # wordcode type, so we need to test skipping them separately.
+  fn() {
+    setopt localtraps localoptions debugbeforecmd
+    trap '(( LINENO == 4 )) && setopt errexit' DEBUG
+    x=three
+    x=four
+    print $LINENO $x
+    [[ -o errexit ]] && print "Hey, ERREXIT is set!"
+  }
+  fn
+1:Skip assignment from DEBUG trap
+>5 three
+
 %clean
 
   rm -f TRAPEXIT


-- 
Peter Stephenson <p.w.stephenson@ntlworld.com>
Web page now at http://homepage.ntlworld.com/p.w.stephenson/