diff options
| -rw-r--r-- | CONTRIBUTING.md | 6 | ||||
| -rw-r--r-- | tests/tests.rs | 33 |
2 files changed, 32 insertions, 7 deletions
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md index ae72afb6..716217e0 100644 --- a/CONTRIBUTING.md +++ b/CONTRIBUTING.md @@ -125,6 +125,12 @@ the expected bindings with `bindgen`'s current output: $ BINDGEN_OVERWRITE_EXPECTED=1 cargo test ``` +If you set the BINDGEN_TESTS_DIFFTOOL environment variable, `cargo test` will +execute $BINDGEN_TESTS_DIFFTOOL /path/of/expected/output /path/of/actual/output +when the expected output differs from the actual output. You can use this to +hand check differences by setting it to e.g. "meld" (assuming you have meld +installed). + If you're not changing command line arguments, you may want to set `BINDGEN_DISABLE_ROUNDTRIP_TEST` to avoid a lot of tests for round-tripping of those. diff --git a/tests/tests.rs b/tests/tests.rs index f8419b53..8b5a91f7 100644 --- a/tests/tests.rs +++ b/tests/tests.rs @@ -174,7 +174,7 @@ fn compare_generated_header( expectation.push(file_name); expectation.set_extension("rs"); expectation_file = fs::File::open(&expectation).ok(); - looked_at.push(expectation); + looked_at.push(expectation.clone()); } let mut expected = String::new(); @@ -233,14 +233,33 @@ fn compare_generated_header( } } - // Overwrite the expectation with actual output. - if env::var_os("BINDGEN_OVERWRITE_EXPECTED").is_some() { - let mut expectation_file = - fs::File::create(looked_at.last().unwrap())?; - expectation_file.write_all(actual.as_bytes())?; + if let Some(var) = env::var_os("BINDGEN_OVERWRITE_EXPECTED") { + if var == "1" { + // Overwrite the expectation with actual output. + let mut expectation_file = + fs::File::create(looked_at.last().unwrap())?; + expectation_file.write_all(actual.as_bytes())?; + } else if var != "0" && var != "" { + panic!("Invalid value of BINDGEN_OVERWRITE_EXPECTED"); + } + } + + if let Some(var) = env::var_os("BINDGEN_TESTS_DIFFTOOL") { + //usecase: var = "meld" -> You can hand check differences + let filename = match header.components().last() { + Some(std::path::Component::Normal(name)) => name, + _ => panic!("Why is the header variable so weird?"), + }; + let actual_result_path = + PathBuf::from(env::var("OUT_DIR").unwrap()).join(filename); + let mut actual_result_file = fs::File::create(&actual_result_path)?; + actual_result_file.write_all(actual.as_bytes())?; + std::process::Command::new(var) + .args(&[looked_at.last().unwrap(), &actual_result_path]) + .output()?; } - return Err(Error::new(ErrorKind::Other, "Header and binding differ! Run with BINDGEN_OVERWRITE_EXPECTED=1 in the environment to automatically overwrite the expectation.")); + return Err(Error::new(ErrorKind::Other, "Header and binding differ! Run with BINDGEN_OVERWRITE_EXPECTED=1 in the environment to automatically overwrite the expectation or with BINDGEN_TESTS_DIFFTOOL=meld to do this manually.")); } if check_roundtrip { |