Improve stopping at errors. (#2278)

In some cases the debugger catches (reports) the same
exception multiple times. This is confusing since these
not new errors. This patch fixes this behaviour.

JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg zherczeg.u-szeged@partner.samsung.com

jerry-core/debugger/debugger.c

@@ -155,7 +155,7 @@ jerry_debugger_send_eval (const lit_utf8_byte_t *eval_string_p, /**< evaluated s
   {
     if (eval_string_p[0] != JERRY_DEBUGGER_EVAL_EVAL)
     {
-      JERRY_DEBUGGER_SET_FLAGS (JERRY_DEBUGGER_THROW_ERROR_FLAG);
+      JERRY_DEBUGGER_SET_FLAGS (JERRY_DEBUGGER_VM_EXCEPTION_THROWN);
       JERRY_CONTEXT (error_value) = result;
 
       /* Stop where the error is caught. */
@@ -709,7 +709,7 @@ jerry_debugger_breakpoint_hit (uint8_t message_type) /**< message type */
     return;
   }
 
-  JERRY_DEBUGGER_UPDATE_FLAGS (JERRY_DEBUGGER_BREAKPOINT_MODE, JERRY_DEBUGGER_THROW_ERROR_FLAG);
+  JERRY_DEBUGGER_UPDATE_FLAGS (JERRY_DEBUGGER_BREAKPOINT_MODE, JERRY_DEBUGGER_VM_EXCEPTION_THROWN);
 
   jerry_debugger_uint8_data_t *uint8_data = NULL;
 

jerry-core/debugger/debugger.h

@@ -98,13 +98,13 @@ typedef enum
   JERRY_DEBUGGER_BREAKPOINT_MODE = 1u << 1, /**< debugger waiting at a breakpoint */
   JERRY_DEBUGGER_VM_STOP = 1u << 2, /**< stop at the next breakpoint even if disabled */
   JERRY_DEBUGGER_VM_IGNORE = 1u << 3, /**< ignore all breakpoints */
-  JERRY_DEBUGGER_VM_IGNORE_EXCEPTION = 1u << 4, /**< debugger stop at an exception */
+  JERRY_DEBUGGER_VM_IGNORE_EXCEPTION = 1u << 4, /**< debugger doesn't stop at any exception */
-  JERRY_DEBUGGER_PARSER_WAIT = 1u << 5, /**< debugger should wait after parsing is completed */
+  JERRY_DEBUGGER_VM_EXCEPTION_THROWN = 1u << 5, /**< no need to stop for this exception */
-  JERRY_DEBUGGER_PARSER_WAIT_MODE = 1u << 6, /**< debugger is waiting after parsing is completed */
+  JERRY_DEBUGGER_PARSER_WAIT = 1u << 6, /**< debugger should wait after parsing is completed */
-  JERRY_DEBUGGER_CLIENT_SOURCE_MODE = 1u << 7, /**< debugger waiting for client code */
+  JERRY_DEBUGGER_PARSER_WAIT_MODE = 1u << 7, /**< debugger is waiting after parsing is completed */
-  JERRY_DEBUGGER_CLIENT_NO_SOURCE = 1u << 8, /**< debugger leaving the client source loop */
+  JERRY_DEBUGGER_CLIENT_SOURCE_MODE = 1u << 8, /**< debugger waiting for client code */
-  JERRY_DEBUGGER_CONTEXT_RESET_MODE = 1u << 9, /**< debugger and engine reinitialization mode */
+  JERRY_DEBUGGER_CLIENT_NO_SOURCE = 1u << 9, /**< debugger leaving the client source loop */
-  JERRY_DEBUGGER_THROW_ERROR_FLAG = 1u << 10, /**< debugger client sent an error throw */
+  JERRY_DEBUGGER_CONTEXT_RESET_MODE = 1u << 10, /**< debugger and engine reinitialization mode */
 } jerry_debugger_flags_t;
 
 /**

jerry-core/ecma/operations/ecma-function-object.c

@@ -566,6 +566,12 @@ ecma_op_function_call (ecma_object_t *func_obj_p, /**< Function object */
       JERRY_CONTEXT (error_value) = ecma_clear_error_reference (ret_value, true);
       ret_value = ECMA_VALUE_ERROR;
     }
+    else
+    {
+#ifdef JERRY_DEBUGGER
+      JERRY_DEBUGGER_CLEAR_FLAGS (JERRY_DEBUGGER_VM_EXCEPTION_THROWN);
+#endif /* JERRY_DEBUGGER */
+    }
   }
   else
   {

jerry-core/vm/vm.c

@@ -2472,6 +2472,10 @@ vm_loop (vm_frame_ctx_t *frame_ctx_p) /**< frame context */
                                   PARSER_TRY_CONTEXT_STACK_ALLOCATION);
               stack_top_p -= PARSER_TRY_CONTEXT_STACK_ALLOCATION;
               result = ECMA_VALUE_ERROR;
+
+#ifdef JERRY_DEBUGGER
+              JERRY_DEBUGGER_SET_FLAGS (JERRY_DEBUGGER_VM_EXCEPTION_THROWN);
+#endif /* JERRY_DEBUGGER */
               goto error;
             }
             case VM_CONTEXT_FINALLY_RETURN:
@@ -2530,7 +2534,7 @@ vm_loop (vm_frame_ctx_t *frame_ctx_p) /**< frame context */
           frame_ctx_p->byte_code_p = byte_code_start_p;
 
           jerry_debugger_breakpoint_hit (JERRY_DEBUGGER_BREAKPOINT_HIT);
-          if (JERRY_CONTEXT (debugger_flags) & JERRY_DEBUGGER_THROW_ERROR_FLAG)
+          if (JERRY_CONTEXT (debugger_flags) & JERRY_DEBUGGER_VM_EXCEPTION_THROWN)
           {
             result = ECMA_VALUE_ERROR;
             goto error;
@@ -2557,7 +2561,7 @@ vm_loop (vm_frame_ctx_t *frame_ctx_p) /**< frame context */
                   || JERRY_CONTEXT (debugger_stop_context) == JERRY_CONTEXT (vm_top_context_p)))
           {
             jerry_debugger_breakpoint_hit (JERRY_DEBUGGER_BREAKPOINT_HIT);
-            if (JERRY_CONTEXT (debugger_flags) & JERRY_DEBUGGER_THROW_ERROR_FLAG)
+            if (JERRY_CONTEXT (debugger_flags) & JERRY_DEBUGGER_VM_EXCEPTION_THROWN)
             {
               result = ECMA_VALUE_ERROR;
               goto error;
@@ -2583,7 +2587,7 @@ vm_loop (vm_frame_ctx_t *frame_ctx_p) /**< frame context */
                   || JERRY_CONTEXT (debugger_stop_context) == JERRY_CONTEXT (vm_top_context_p)))
           {
             jerry_debugger_breakpoint_hit (JERRY_DEBUGGER_BREAKPOINT_HIT);
-            if (JERRY_CONTEXT (debugger_flags) & JERRY_DEBUGGER_THROW_ERROR_FLAG)
+            if (JERRY_CONTEXT (debugger_flags) & JERRY_DEBUGGER_VM_EXCEPTION_THROWN)
             {
               result = ECMA_VALUE_ERROR;
               goto error;
@@ -2725,7 +2729,7 @@ error:
 #ifdef JERRY_DEBUGGER
       const uint32_t dont_stop = (JERRY_DEBUGGER_VM_IGNORE_EXCEPTION
                                   | JERRY_DEBUGGER_VM_IGNORE
-                                  | JERRY_DEBUGGER_THROW_ERROR_FLAG);
+                                  | JERRY_DEBUGGER_VM_EXCEPTION_THROWN);
 
       if ((JERRY_CONTEXT (debugger_flags) & JERRY_DEBUGGER_CONNECTED)
           && !(frame_ctx_p->bytecode_header_p->status_flags & CBC_CODE_FLAGS_DEBUGGER_IGNORE)
@@ -2739,7 +2743,7 @@ error:
         {
           jerry_debugger_breakpoint_hit (JERRY_DEBUGGER_EXCEPTION_HIT);
 
-          if (JERRY_CONTEXT (debugger_flags) & JERRY_DEBUGGER_THROW_ERROR_FLAG)
+          if (JERRY_CONTEXT (debugger_flags) & JERRY_DEBUGGER_VM_EXCEPTION_THROWN)
           {
             ecma_free_value (current_error_value);
           }
@@ -2747,6 +2751,8 @@ error:
           {
             JERRY_CONTEXT (error_value) = current_error_value;
           }
+
+          JERRY_DEBUGGER_SET_FLAGS (JERRY_DEBUGGER_VM_EXCEPTION_THROWN);
         }
       }
 #endif /* JERRY_DEBUGGER */
@@ -2786,6 +2792,10 @@ error:
       {
         JERRY_ASSERT (frame_ctx_p->registers_p + register_end + frame_ctx_p->context_depth == stack_top_p);
 
+#ifdef JERRY_DEBUGGER
+        JERRY_DEBUGGER_CLEAR_FLAGS (JERRY_DEBUGGER_VM_EXCEPTION_THROWN);
+#endif /* JERRY_DEBUGGER */
+
         byte_code_p = frame_ctx_p->byte_code_p;
 
         if (VM_GET_CONTEXT_TYPE (stack_top_p[-1]) == VM_CONTEXT_CATCH)

tests/debugger/do_throw_adv.cmd

@@ -0,0 +1,11 @@
+c
+s
+c
+c
+c
+c
+c
+c
+c
+c
+c

tests/debugger/do_throw_adv.expected

@@ -0,0 +1,42 @@
+Connecting to: localhost:5001
+Stopped at tests/debugger/do_throw_adv.js:15
+(jerry-debugger) c
+Exception throw detected (to disable automatic stop type exception 0)
+Exception hint: 2
+Stopped at tests/debugger/do_throw_adv.js:18 (in f() at line:17, col:1)
+(jerry-debugger) s
+Stopped at tests/debugger/do_throw_adv.js:32
+(jerry-debugger) c
+Exception throw detected (to disable automatic stop type exception 0)
+Exception hint: 4
+Stopped at tests/debugger/do_throw_adv.js:18 (in f() at line:17, col:1)
+(jerry-debugger) c
+Exception throw detected (to disable automatic stop type exception 0)
+Exception hint: Catch again
+Stopped at tests/debugger/do_throw_adv.js:41
+(jerry-debugger) c
+Exception throw detected (to disable automatic stop type exception 0)
+Exception hint: 7
+Stopped at tests/debugger/do_throw_adv.js:18 (in f() at line:17, col:1)
+(jerry-debugger) c
+Exception throw detected (to disable automatic stop type exception 0)
+Exception hint: 10
+Stopped at tests/debugger/do_throw_adv.js:18 (in f() at line:17, col:1)
+(jerry-debugger) c
+Exception throw detected (to disable automatic stop type exception 0)
+Exception hint: Replace the other error
+Stopped at tests/debugger/do_throw_adv.js:63
+(jerry-debugger) c
+Exception throw detected (to disable automatic stop type exception 0)
+Exception hint: 13
+Stopped at tests/debugger/do_throw_adv.js:18 (in f() at line:17, col:1)
+(jerry-debugger) c
+Exception throw detected (to disable automatic stop type exception 0)
+Exception hint: Should be caught
+Stopped at tests/debugger/do_throw_adv.js:76
+(jerry-debugger) c
+Exception throw detected (to disable automatic stop type exception 0)
+Exception hint: 16
+Stopped at tests/debugger/do_throw_adv.js:18 (in f() at line:17, col:1)
+(jerry-debugger) c
+err: Script Error: 16

tests/debugger/do_throw_adv.js

@@ -0,0 +1,81 @@
+// Copyright JS Foundation and other contributors, http://js.foundation
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+var a = 1;
+
+function f() {
+  throw ++a;
+}
+
+function g() {
+  f();
+}
+
+function h() {
+  g();
+}
+
+try {
+  h();
+} catch (e) {
+  ++a;
+}
+
+try {
+  h();
+} catch (e) {
+  ++a;
+
+  try {
+    throw "Catch again";
+  } catch (e) {
+    ++a;
+  }
+}
+
+try {
+  try {
+    h();
+  } finally {
+    ++a;
+  }
+  ++a; /* Should not happen. */
+} catch (e) {
+  ++a;
+}
+
+try {
+  try {
+    h();
+  } finally {
+    ++a;
+    throw "Replace the other error";
+  }
+} catch (e) {
+  ++a;
+}
+
+try {
+  break_try_label: try {
+    h();
+  } finally {
+    ++a;
+    break break_try_label;
+  }
+  throw "Should be caught";
+} catch (e) {
+  ++a;
+}
+
+h();