Replace OutputConflictHandling enum with function pointers instead

Author: oli-obk

CHANGELOG.md

@@ -15,6 +15,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 * `only`/`ignore` filters now only accept integers, alphabetic characters, `-` and `_`
 * `only`/ `ignore` filters allow comments by ignoring everything from an `#` onwards
+* `OutputConflictHandling` has been replaced by `error_on_output_conflict`, `bless_output_files`,
+    and `ignore_output_conflict` functions. Custom functions can now be used to implement special
+    handling of output conflicts.
 
 ### Removed
 

src/config.rs

@@ -10,7 +10,7 @@ use crate::{
     diagnostics::Diagnostics,
     parser::CommandParserFunc,
     per_test_config::{Comments, Condition},
-    CommandBuilder,
+    CommandBuilder, Error, Errors,
 };
 pub use color_eyre;
 use color_eyre::eyre::Result;
@@ -36,7 +36,8 @@ pub struct Config {
     /// The binary to actually execute.
     pub program: CommandBuilder,
     /// What to do in case the stdout/stderr output differs from the expected one.
-    pub output_conflict_handling: OutputConflictHandling,
+    pub output_conflict_handling:
+        fn(path: &Path, actual: Vec<u8>, errors: &mut Errors, config: &Config),
     /// The recommended command to bless failing tests.
     pub bless_command: Option<String>,
     /// Where to dump files like the binaries compiled from tests.
@@ -78,7 +79,7 @@ impl Config {
             target: Default::default(),
             root_dir: Default::default(),
             program: CommandBuilder::cmd(""),
-            output_conflict_handling: OutputConflictHandling::Error,
+            output_conflict_handling: error_on_output_conflict,
             bless_command: Default::default(),
             out_dir: Default::default(),
             skip_files: Default::default(),
@@ -159,7 +160,7 @@ impl Config {
             target: None,
             root_dir: root_dir.into(),
             program: CommandBuilder::rustc(),
-            output_conflict_handling: OutputConflictHandling::Error,
+            output_conflict_handling: error_on_output_conflict,
             bless_command: None,
             out_dir: std::env::var_os("CARGO_TARGET_DIR")
                 .map(PathBuf::from)
@@ -273,9 +274,9 @@ impl Config {
         self.list = list;
 
         if check {
-            self.output_conflict_handling = OutputConflictHandling::Error;
+            self.output_conflict_handling = error_on_output_conflict;
         } else if bless {
-            self.output_conflict_handling = OutputConflictHandling::Bless;
+            self.output_conflict_handling = bless_output_files;
         }
     }
 
@@ -437,16 +438,41 @@ impl Config {
     }
 }
 
-#[derive(Debug, Clone)]
-/// The different options for what to do when stdout/stderr files differ from the actual output.
-pub enum OutputConflictHandling {
-    /// Fail the test when mismatches are found, if provided the command string
-    /// in [`Config::bless_command`] will be suggested as a way to bless the
-    /// test.
-    Error,
-    /// Ignore mismatches in the stderr/stdout files.
-    Ignore,
-    /// Instead of erroring if the stderr/stdout differs from the expected
-    /// automatically replace it with the found output (after applying filters).
-    Bless,
+/// Fail the test when mismatches are found, if provided the command string
+/// in [`Config::bless_command`] will be suggested as a way to bless the
+/// test.
+pub fn error_on_output_conflict(
+    path: &Path,
+    actual: Vec<u8>,
+    errors: &mut Errors,
+    config: &Config,
+) {
+    let expected = std::fs::read(path).unwrap_or_default();
+    if actual != expected {
+        errors.push(Error::OutputDiffers {
+            path: path.to_path_buf(),
+            actual,
+            expected,
+            bless_command: config.bless_command.clone(),
+        });
+    }
+}
+
+/// Ignore mismatches in the stderr/stdout files.
+pub fn ignore_output_conflict(
+    _path: &Path,
+    _actual: Vec<u8>,
+    _errors: &mut Errors,
+    _config: &Config,
+) {
+}
+
+/// Instead of erroring if the stderr/stdout differs from the expected
+/// automatically replace it with the found output (after applying filters).
+pub fn bless_output_files(path: &Path, actual: Vec<u8>, _errors: &mut Errors, _config: &Config) {
+    if actual.is_empty() {
+        let _ = std::fs::remove_file(path);
+    } else {
+        std::fs::write(path, &actual).unwrap();
+    }
 }

src/dependencies.rs

@@ -16,7 +16,7 @@ use crate::{
     custom_flags::Flag,
     per_test_config::TestConfig,
     test_result::Errored,
-    CommandBuilder, Config, OutputConflictHandling,
+    CommandBuilder, Config,
 };
 
 #[derive(Default, Debug)]
@@ -100,12 +100,11 @@ fn build_dependencies_inner(
 
     // Reusable closure for setting up the environment both for artifact generation and `cargo_metadata`
     let set_locking = |cmd: &mut Command| {
-        if let OutputConflictHandling::Error = config.output_conflict_handling {
+        if !info.bless_lockfile {
             cmd.arg("--locked");
         }
     };
 
-    set_locking(&mut build);
     build.arg("--message-format=json");
 
     let output = match build.output() {
@@ -365,6 +364,8 @@ pub struct DependencyBuilder {
     /// Build with [`build-std`](https://doc.rust-lang.org/1.78.0/cargo/reference/unstable.html#build-std),
     /// which requires the nightly toolchain. The [`String`] can contain the standard library crates to build.
     pub build_std: Option<String>,
+    /// Whether the lockfile can be overwritten
+    pub bless_lockfile: bool,
 }
 
 impl Default for DependencyBuilder {
@@ -373,6 +374,7 @@ impl Default for DependencyBuilder {
             crate_manifest_path: PathBuf::from("Cargo.toml"),
             program: CommandBuilder::cargo(),
             build_std: None,
+            bless_lockfile: false,
         }
     }
 }

src/per_test_config.rs

@@ -20,7 +20,7 @@ pub use crate::parser::{Comments, Condition, Revisioned};
 use crate::parser::{ErrorMatch, ErrorMatchKind, OptWithLine};
 use crate::status_emitter::{SilentStatus, TestStatus};
 use crate::test_result::{Errored, TestOk, TestResult};
-use crate::{core::strip_path_prefix, Config, Error, Errors, OutputConflictHandling};
+use crate::{core::strip_path_prefix, Config, Error, Errors};
 
 /// All information needed to run a single test
 pub struct TestConfig {
@@ -200,27 +200,7 @@ impl TestConfig {
     pub(crate) fn check_output(&self, output: &[u8], errors: &mut Errors, kind: &str) -> PathBuf {
         let output = self.normalize(output, kind);
         let path = self.output_path(kind);
-        match &self.config.output_conflict_handling {
-            OutputConflictHandling::Error => {
-                let expected_output = std::fs::read(&path).unwrap_or_default();
-                if output != expected_output {
-                    errors.push(Error::OutputDiffers {
-                        path: path.clone(),
-                        actual: output.clone(),
-                        expected: expected_output,
-                        bless_command: self.config.bless_command.clone(),
-                    });
-                }
-            }
-            OutputConflictHandling::Bless => {
-                if output.is_empty() {
-                    let _ = std::fs::remove_file(&path);
-                } else {
-                    std::fs::write(&path, &output).unwrap();
-                }
-            }
-            OutputConflictHandling::Ignore => {}
-        }
+        (self.config.output_conflict_handling)(&path, output, errors, &self.config);
         path
     }
 

tests/integrations/basic-bin/tests/ui_tests.rs

@@ -4,9 +4,9 @@ fn main() -> ui_test::color_eyre::Result<()> {
     let path = "../../../target";
     let mut config = Config {
         output_conflict_handling: if std::env::var_os("BLESS").is_some() {
-            OutputConflictHandling::Bless
+            ui_test::bless_output_files
         } else {
-            OutputConflictHandling::Error
+            ui_test::error_on_output_conflict
         },
         bless_command: Some("cargo test".to_string()),
         ..Config::rustc("tests/actual_tests")

tests/integrations/basic-fail-mode/tests/ui_tests.rs

@@ -4,9 +4,9 @@ fn main() -> ui_test::color_eyre::Result<()> {
     let path = "../../../target";
     let mut config = Config {
         output_conflict_handling: if std::env::var_os("BLESS").is_some() {
-            OutputConflictHandling::Bless
+            ui_test::bless_output_files
         } else {
-            OutputConflictHandling::Error
+            ui_test::error_on_output_conflict
         },
         bless_command: Some("cargo test".to_string()),
         ..Config::rustc("tests/actual_tests")

tests/integrations/basic-fail/tests/ui_tests.rs

@@ -4,7 +4,7 @@ fn main() -> ui_test::color_eyre::Result<()> {
     let path = "../../../target";
     let mut config = Config {
         // Never bless integrations-fail tests, we want to see stderr mismatches
-        output_conflict_handling: OutputConflictHandling::Error,
+        output_conflict_handling: ui_test::error_on_output_conflict,
         bless_command: Some("DO NOT BLESS. These are meant to fail".to_string()),
         ..Config::rustc("tests/actual_tests")
     };

tests/integrations/basic-fail/tests/ui_tests_bless.rs

@@ -14,9 +14,9 @@ fn main() -> ui_test::color_eyre::Result<()> {
 
         let mut config = Config {
             output_conflict_handling: if std::env::var_os("BLESS").is_some() {
-                OutputConflictHandling::Bless
+                ui_test::bless_output_files
             } else {
-                OutputConflictHandling::Error
+                ui_test::error_on_output_conflict
             },
             bless_command: Some("cargo test".to_string()),
             ..Config::rustc(root_dir)

tests/integrations/basic-fail/tests/ui_tests_diff_only.rs

@@ -3,7 +3,7 @@ use ui_test::*;
 fn main() -> ui_test::color_eyre::Result<()> {
     let config = Config {
         // Never bless integrations-fail tests, we want to see stderr mismatches
-        output_conflict_handling: OutputConflictHandling::Error,
+        output_conflict_handling: ui_test::error_on_output_conflict,
         bless_command: Some("DO NOT BLESS. These are meant to fail".to_string()),
         ..Config::rustc("tests/actual_tests")
     };

tests/integrations/basic-fail/tests/ui_tests_invalid_program.rs

@@ -4,7 +4,7 @@ fn main() -> ui_test::color_eyre::Result<()> {
     let config = Config {
         program: CommandBuilder::cmd("invalid_foobarlaksdfalsdfj"),
         // Never bless integrations-fail tests, we want to see stderr mismatches
-        output_conflict_handling: OutputConflictHandling::Error,
+        output_conflict_handling: ui_test::error_on_output_conflict,
         bless_command: Some("DO NOT BLESS. These are meant to fail".to_string()),
         ..Config::rustc("tests/actual_tests")
     };