genhtml can't find Java source files when generating a coverage report

[hanwen]

Please provide the following information. The more we know about your system and use case, the more easily and likely we can help.

Description of the problem / feature request / question:

$ git clone --recursive https://gerrit.googlesource.com/gerrit

$ cd gerrit

$ bazel version
Build label: 0.4.4
Build target: bazel-out/local-fastbuild/bin/src/main/java/com/google/devtools/build/lib/bazel/BazelServer_deploy.jar
Build time: Wed Feb 1 18:54:21 2017 (1485975261)
Build timestamp: 1485975261
Build timestamp as int: 1485975261

$ bazel coverage --test_output=streamed //gerrit-common:auto_value_tests
.........
WARNING: Streamed test output requested so all tests will be run locally, without sharding, one at a time.
INFO: Using default value for --instrumentation_filter: "//gerrit-common".
INFO: Override the above default with --instrumentation_filter
INFO: Found 1 test target...
JUnit4 Test Runner
.
Time: 0.027

OK (1 test)

BazelTestRunner exiting with a return value of 0
JVM shutdown hooks (if any) will run now.
The JVM will exit once they complete.

-- JVM shutdown starting at 2017-02-13 15:38:40 --

Exception in thread "main" java.lang.UnsupportedClassVersionError: com/google/devtools/lcovmerger/Main : Unsupported major.minor version 52.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:803)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:442)
at java.net.URLClassLoader.access$100(URLClassLoader.java:64)
at java.net.URLClassLoader$1.run(URLClassLoader.java:354)
at java.net.URLClassLoader$1.run(URLClassLoader.java:348)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:347)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.java:482)
FAIL: //gerrit-common:auto_value_tests (see /home/hanwen/.cache/bazel/_bazel_hanwen/9590700e58e6cc9bff046cc6a346bc64/execroot/gerrit/bazel-out/local-fastbuild/testlogs/gerrit-common/auto_value_tests/test.log).
Target //gerrit-common:auto_value_tests up-to-date:
bazel-bin/gerrit-common/auto_value_tests.jar
bazel-bin/gerrit-common/auto_value_tests

If asking a question or requesting a feature, also tell us about the underlying problem you're trying to solve.

If possible, provide a minimal example to reproduce the problem:

Environment info

• Operating System:

• Bazel version (output of bazel info release):

• If bazel info release returns "development version" or "(@Non-Git)", please tell us what source tree you compiled Bazel from; git commit hash is appreciated (git rev-parse HEAD):

Have you found anything relevant by searching the web? (e.g. GitHub issues, email threads in the bazel-discuss@googlegroups.com archive)

Anything else, information or logs or outputs that would be helpful?

(If they are large, please upload as attachment or provide link).

[hanwen]

@hermione521

[hanwen]

this is on ubuntu (google laptop version)

[hanwen]

on my workstation

$ bazel coverage --test_strategy=standalone --test_output=streamed //gerrit-common:auto_value_tests
WARNING: Streamed test output requested so all tests will be run locally, without sharding, one at a time.
INFO: Using default value for --instrumentation_filter: "//gerrit-common".
INFO: Override the above default with --instrumentation_filter
INFO: Found 1 test target...
JUnit4 Test Runner
.
Time: 0.031

OK (1 test)

BazelTestRunner exiting with a return value of 0
JVM shutdown hooks (if any) will run now.
The JVM will exit once they complete.

-- JVM shutdown starting at 2017-02-13 15:43:31 --

Feb 13, 2017 3:43:31 PM com.google.devtools.lcovmerger.LcovMerger merge
SEVERE: No lcov file found.
FAIL: //gerrit-common:auto_value_tests (see /usr/local/google/home/hanwen/.cache/bazel/_bazel_hanwen/b05cca6a859569ffdc923a4aef4e793e/execroot/gerrit/bazel-out/local-fastbuild/testlogs/gerrit-common/auto_value_tests/test.log).
Target //gerrit-common:auto_value_tests up-to-date:
bazel-bin/gerrit-common/auto_value_tests.jar
bazel-bin/gerrit-common/auto_value_tests
INFO: Elapsed time: 0.837s, Critical Path: 0.51s
//gerrit-common:auto_value_tests FAILED in 1 out of 2 in 0.5s
/usr/local/google/home/hanwen/.cache/bazel/_bazel_hanwen/b05cca6a859569ffdc923a4aef4e793e/execroot/gerrit/bazel-out/local-fastbuild/testlogs/gerrit-common/auto_value_tests/test.log

[hanwen]

in the latter case, there is a coverage.dat file, but it is empty. Do we need to tweak the test runner somehow to generate the coverage file?

[hanwen]

(i'm sorry, these are really two bugs. I'm personally more interested in the latter problem.)

[hermione521]

quick update: it's not supported now

bazel/src/main/java/com/google/devtools/build/lib/rules/java/JavaCompilationHelper.java

Line 291 in 67f0f4b

// TODO(bazel-team): What about source jars?

I'll check how to make it happen.

[hanwen]

for now, I'd be satisfied if we could just skip the srcjar. They're only used for autovalue, so they shouldn't affect the coverage much.

[hanwen]

ping? could you provide a time estimate and/or a workaround?

[hermione521]

Sorry, I'm focused on benchmark now. But I will do it before I leave! (which means next month)

[ulfjack]

The auto_value_tests doesn't have any code for which Bazel could collect coverage. I'm not sure why we report an error if there's no coverage, I think in Blaze we're only reporting a warning.

In any case, I looked for a test that does have sources:

$ bazel coverage //gerrit-sshd:sshd_tests

This gives more interesting output. The test is marked as passed, but there's a stack trace in the log:

Exception in thread "Thread-0" java.lang.VerifyError: Bad type on operand stack
Exception Details:
Location:
com/google/testing/coverage/BranchDetailAnalyzer.mapProbes(Lorg/objectweb/asm/ClassReader;)Ljava/util/Map; @21: invokevirtual
Reason:
Type 'org/jacoco/core/internal/flow/ClassProbesAdapter' (current frame, stack[1]) is not assignable to 'org/objectweb/asm/ClassVisitor'
Current Frame:
bci: @21
flags: { }
locals: { 'com/google/testing/coverage/BranchDetailAnalyzer', 'org/objectweb/asm/ClassReader', 'com/google/testing/coverage/ClassProbesMapper', 'org/jacoco/core/internal/flow/ClassProbesAdapter' }
stack: { 'org/objectweb/asm/ClassReader', 'org/jacoco/core/internal/flow/ClassProbesAdapter', integer }
Bytecode:
0x0000000: bb00 2459 b700 254d bb00 2659 2c03 b700
0x0000010: 274e 2b2d 03b6 0028 2cb6 0029 b0

at com.google.testing.coverage.JacocoCoverageRunner.analyzeBranch(JacocoCoverageRunner.java:138)
at com.google.testing.coverage.JacocoCoverageRunner.create(JacocoCoverageRunner.java:84)
at com.google.testing.coverage.JacocoCoverageRunner$2.run(JacocoCoverageRunner.java:258)

That's certainly a bug, but I have no idea where that might be coming from.