Re: Loops and pipes

[Philippe Altherr <philippe.altherr@xxxxxxxxx>]

Here is an alternate version of the second patch that emits a warning rather than an error when breaking/continuing beyond the outermost loop in the same subshell. This version also prevents "continue" from continuing the outermost loop when continuing beyond it. The following script will only print A (and a warning), while it currently prints A, B, and C.

for X in A B C; do

  echo $X

  continue 2

done

- Warn when escaping past all enclosing loops in the same subshell

Philippe

diff --git a/Src/builtin.c b/Src/builtin.c
index 4d47227ab..0d1a0058f 100644
--- a/Src/builtin.c
+++ b/Src/builtin.c
@@ -5824,13 +5824,19 @@ bin_break(char *name, char **argv, UNUSED(Options ops), int func)
 	    zerrnam(name, "argument is not positive: %d", num);
 	    return 1;
 	}
-	if (!loops) {   /* break/continue only permitted in loops */
+	if (!loops) {
 	    zerrnam(name, ancestor_loops
 		    ? "not in same subshell as first enclosing loop"
 		    : "not in for, while, until, select, or repeat loop");
 	    return 1;
 	}
-	contflag = func == BIN_CONTINUE;
+	if (num > loops) {
+	    zwarnnam(name, ancestor_loops
+		     ? "not in same subshell as first %d enclosing loops"
+		     : "not in %d for, while, until, select, or repeat loops",
+		     num);
+	}
+	contflag = func == BIN_CONTINUE && num <= loops;
 	breaks = minimum(num, loops);
 	break;
     case BIN_RETURN:
diff --git a/Test/A07control.ztst b/Test/A07control.ztst
index 6054a363d..33281929e 100644
--- a/Test/A07control.ztst
+++ b/Test/A07control.ztst
@@ -37,16 +37,138 @@
 1:continue outside loop
 ?fn:continue:1: not in for, while, until, select, or repeat loop
 
-  for x in a b c; do
-    ( echo $x:before; continue 2>&1; echo $x:after )
-  done
-1:continue in subshell
->a:before
->(eval):continue:2: not in same subshell as first enclosing loop
->b:before
->(eval):continue:2: not in same subshell as first enclosing loop
->c:before
->(eval):continue:2: not in same subshell as first enclosing loop
+  local cmd script=()
+  for cmd in "break 2" "break 3" "break 4" "continue 2" "continue 3" "continue 4"; do
+    script+='
+      echo "Testing \"'$cmd'\":"
+      for X in A B; do
+        for Y in p q; do
+          for Z in 1 2; do
+            echo "'$cmd': $X$Y$Z before"
+            '$cmd' 2>&1
+            echo "'$cmd': $X$Y$Z after"
+          done
+          echo "'$cmd': $X$Y- after"
+        done
+        echo "'$cmd': $X-- after"
+      done
+      echo "'$cmd': --- after"
+    '
+  done
+  $ZTST_testdir/../Src/zsh -fc "$script"
+0:break/continue beneath, at, and beyond the outermost loop
+>Testing "break 2":
+>break 2: Ap1 before
+>break 2: A-- after
+>break 2: Bp1 before
+>break 2: B-- after
+>break 2: --- after
+>Testing "break 3":
+>break 3: Ap1 before
+>break 3: --- after
+>Testing "break 4":
+>break 4: Ap1 before
+>zsh:break:35: not in 4 for, while, until, select, or repeat loops
+>break 4: --- after
+>Testing "continue 2":
+>continue 2: Ap1 before
+>continue 2: Aq1 before
+>continue 2: A-- after
+>continue 2: Bp1 before
+>continue 2: Bq1 before
+>continue 2: B-- after
+>continue 2: --- after
+>Testing "continue 3":
+>continue 3: Ap1 before
+>continue 3: Bp1 before
+>continue 3: --- after
+>Testing "continue 4":
+>continue 4: Ap1 before
+>zsh:continue:77: not in 4 for, while, until, select, or repeat loops
+>continue 4: --- after
+
+  local cmd X
+  for cmd in "break" "continue"; do
+    echo "Testing \"$cmd\":"
+    for X in A B; do
+      (
+        echo "$cmd: $X before"
+        $cmd 2>&1;
+        echo "$cmd: $X after1"
+      )
+      echo "$cmd: $X after2"
+    done
+  done
+0:break/continue in subshell
+>Testing "break":
+>break: A before
+>(eval):break:7: not in same subshell as first enclosing loop
+>break: A after2
+>break: B before
+>(eval):break:7: not in same subshell as first enclosing loop
+>break: B after2
+>Testing "continue":
+>continue: A before
+>(eval):continue:7: not in same subshell as first enclosing loop
+>continue: A after2
+>continue: B before
+>(eval):continue:7: not in same subshell as first enclosing loop
+>continue: B after2
+
+  local cmd X
+  for cmd in "break 1" "break 2" "break 3" "continue 1" "continue 2" "continue 3"; do
+    echo "Testing \"$cmd\":"
+    for X in A; do
+      (
+        for Y in p q; do
+          for Z in 1 2; do
+            echo "$cmd: $X$Y$Z before"
+            eval $cmd 2>&1
+            echo "$cmd: $X$Y$Z after"
+          done
+          echo "$cmd: $X$Y- after"
+        done
+        echo "$cmd: $X-- after1"
+      )
+      echo "$cmd: $X-- after2"
+    done
+  done
+0:break/continue beneath, at, and beyond the outermost same-subshell loop
+>Testing "break 1":
+>break 1: Ap1 before
+>break 1: Ap- after
+>break 1: Aq1 before
+>break 1: Aq- after
+>break 1: A-- after1
+>break 1: A-- after2
+>Testing "break 2":
+>break 2: Ap1 before
+>break 2: A-- after1
+>break 2: A-- after2
+>Testing "break 3":
+>break 3: Ap1 before
+>(eval):break:1: not in same subshell as first 3 enclosing loops
+>break 3: A-- after1
+>break 3: A-- after2
+>Testing "continue 1":
+>continue 1: Ap1 before
+>continue 1: Ap2 before
+>continue 1: Ap- after
+>continue 1: Aq1 before
+>continue 1: Aq2 before
+>continue 1: Aq- after
+>continue 1: A-- after1
+>continue 1: A-- after2
+>Testing "continue 2":
+>continue 2: Ap1 before
+>continue 2: Aq1 before
+>continue 2: A-- after1
+>continue 2: A-- after2
+>Testing "continue 3":
+>continue 3: Ap1 before
+>(eval):continue:1: not in same subshell as first 3 enclosing loops
+>continue 3: A-- after1
+>continue 3: A-- after2
 
   for outer in 0 1 2 3; do
     print outer $outer