8014781: support Error.captureStackTrace

Reviewed-by: jlaskey, hannesw

nashorn/src/jdk/nashorn/api/scripting/NashornException.java

@@ -25,6 +25,9 @@
 
 package jdk.nashorn.api.scripting;
 
+import java.util.ArrayList;
+import java.util.List;
+import jdk.nashorn.internal.codegen.CompilerConstants;
 import jdk.nashorn.internal.runtime.ECMAErrors;
 
 /**
@@ -136,4 +139,52 @@ public abstract class NashornException extends RuntimeException {
         return column;
     }
 
+    /**
+     * Returns array javascript stack frames from the given exception object.
+     *
+     * @param exception exception from which stack frames are retrieved and filtered
+     * @return array of javascript stack frames
+     */
+    public static StackTraceElement[] getScriptFrames(final Throwable exception) {
+        final StackTraceElement[] frames = ((Throwable)exception).getStackTrace();
+        final List<StackTraceElement> filtered = new ArrayList<>();
+        for (final StackTraceElement st : frames) {
+            if (ECMAErrors.isScriptFrame(st)) {
+                final String className = "<" + st.getFileName() + ">";
+                String methodName = st.getMethodName();
+                if (methodName.equals(CompilerConstants.RUN_SCRIPT.symbolName())) {
+                    methodName = "<program>";
+                }
+                filtered.add(new StackTraceElement(className, methodName,
+                        st.getFileName(), st.getLineNumber()));
+            }
+        }
+        return filtered.toArray(new StackTraceElement[filtered.size()]);
+    }
+
+    /**
+     * Return a formatted script stack trace string with frames information separated by '\n'
+     *
+     * @param exception exception for which script stack string is returned
+     * @return formatted stack trace string
+     */
+    public static String getScriptStackString(final Throwable exception) {
+        final StringBuilder buf = new StringBuilder();
+        final StackTraceElement[] frames = getScriptFrames((Throwable)exception);
+        for (final StackTraceElement st : frames) {
+            buf.append(st.getMethodName());
+            buf.append(" @ ");
+            buf.append(st.getFileName());
+            buf.append(':');
+            buf.append(st.getLineNumber());
+            buf.append('\n');
+        }
+        final int len = buf.length();
+        // remove trailing '\n'
+        if (len > 0) {
+            assert buf.charAt(len - 1) == '\n';
+            buf.deleteCharAt(len - 1);
+        }
+        return buf.toString();
+    }
 }

nashorn/src/jdk/nashorn/internal/objects/NativeError.java

@@ -32,6 +32,7 @@ import java.lang.invoke.MethodHandle;
 import java.lang.invoke.MethodHandles;
 import java.util.ArrayList;
 import java.util.List;
+import jdk.nashorn.api.scripting.NashornException;
 import jdk.nashorn.internal.codegen.CompilerConstants;
 import jdk.nashorn.internal.lookup.MethodHandleFactory;
 import jdk.nashorn.internal.objects.annotations.Attribute;
@@ -118,6 +119,20 @@ public final class NativeError extends ScriptObject {
         return new NativeError(msg);
     }
 
+    /**
+     * Nashorn extension: Error.captureStackTrace. Capture stack trace at the point of call into the Error object provided.
+     *
+     * @param self self reference
+     */
+    @Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR)
+    public static Object captureStackTrace(final Object self, final Object errorObj) {
+        Global.checkObject(errorObj);
+        final ScriptObject sobj = (ScriptObject)errorObj;
+        final ECMAException exp = new ECMAException(sobj, null);
+        sobj.set("stack", NashornException.getScriptStackString(exp), false);
+        return UNDEFINED;
+    }
+
     /**
      * Nashorn extension: Error.dumpStack
      * dumps the stack of the current thread.
@@ -163,7 +178,7 @@ public final class NativeError extends ScriptObject {
         final Object exception = ECMAException.getException(sobj);
         Object[] res;
         if (exception instanceof Throwable) {
-            res = getScriptFrames((Throwable)exception);
+            res = NashornException.getScriptFrames((Throwable)exception);
         } else {
             res = ScriptRuntime.EMPTY_ARRAY;
         }
@@ -272,25 +287,8 @@ public final class NativeError extends ScriptObject {
         }
 
         final Object exception = ECMAException.getException(sobj);
-        final StringBuilder buf = new StringBuilder();
         if (exception instanceof Throwable) {
-            final Object[] frames = getScriptFrames((Throwable)exception);
-            for (final Object fr : frames) {
-                final StackTraceElement st = (StackTraceElement)fr;
-                buf.append(st.getMethodName());
-                buf.append(" @ ");
-                buf.append(st.getFileName());
-                buf.append(':');
-                buf.append(st.getLineNumber());
-                buf.append('\n');
-            }
-            final int len = buf.length();
-            // remove trailing '\n'
-            if (len > 0) {
-                assert buf.charAt(len - 1) == '\n';
-                buf.deleteCharAt(len - 1);
-            }
-            return buf.toString();
+            return NashornException.getScriptStackString((Throwable)exception);
         } else {
             return "";
         }
@@ -364,21 +362,4 @@ public final class NativeError extends ScriptObject {
             throw new MethodHandleFactory.LookupException(e);
         }
     }
-
-    private static Object[] getScriptFrames(final Throwable exception) {
-        final StackTraceElement[] frames = ((Throwable)exception).getStackTrace();
-        final List<StackTraceElement> filtered = new ArrayList<>();
-        for (final StackTraceElement st : frames) {
-            if (ECMAErrors.isScriptFrame(st)) {
-                final String className = "<" + st.getFileName() + ">";
-                String methodName = st.getMethodName();
-                if (methodName.equals(CompilerConstants.RUN_SCRIPT.symbolName())) {
-                    methodName = "<program>";
-                }
-                filtered.add(new StackTraceElement(className, methodName,
-                        st.getFileName(), st.getLineNumber()));
-            }
-        }
-        return filtered.toArray();
-    }
 }

nashorn/test/script/basic/JDK-8014781.js

@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ * 
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ * 
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ * 
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ * 
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * JDK-8014781: support Error.captureStackTrace
+ *
+ * @test
+ * @run
+ */
+
+function MyError() {
+    Error.captureStackTrace(this);
+}
+
+function func() {
+    return new MyError();
+}
+
+var e = func();
+print(e.stack.replace(/\\/g, '/'));

nashorn/test/script/basic/JDK-8014781.js.EXPECTED

@@ -0,0 +1,3 @@
+MyError @ test/script/basic/JDK-8014781.js:32
+func @ test/script/basic/JDK-8014781.js:36
+<program> @ test/script/basic/JDK-8014781.js:39