Add --file

Fixes sourcefrog#28

Cargo.toml

@@ -26,6 +26,7 @@ similar = "2.0"
 subprocess = "0.2.8"
 tempfile = "3.2"
 walkdir = "2.3"
+globset = "0.4.8"
 
 [dependencies.cp_r]
 version = "0.5.1"

NEWS.md

@@ -2,6 +2,9 @@
 
 ## Unreleased
 
+- New `--file` command line option to mutate only functions in source files
+  matching a glob.
+
 - Improved: Don't attempt to mutate functions called `new` or implementations of
   `Default`. cargo-mutants can not yet generate good mutations for these so they
   are generally false positives.

README.md

@@ -52,6 +52,10 @@ but not adequately tested.
 
 `-d`, `--dir`: Test the Rust tree in the given directory, rather than the default directory.
 
+`-f`, `--file FILE`: Mutate only functions in files matching the given name or
+glob. If the glob contains `/` it matches against the path from the source tree
+root; otherwise it matches only against the file name.
+
 `--list`: Show what mutants could be generated, without running them.
 
 `--diff`: With `--list`, also include a diff of the source change for each mutant.

src/lab.rs

@@ -118,7 +118,7 @@ pub fn test_unmutated_then_all_mutants(
         }
     }
 
-    let mut mutants = source_tree.mutants()?;
+    let mut mutants = source_tree.mutants(&options)?;
     if options.shuffle {
         mutants.shuffle(&mut rand::thread_rng());
     }

src/main.rs

@@ -16,6 +16,7 @@ mod source;
 mod textedit;
 mod visit;
 
+use std::convert::TryFrom;
 use std::env;
 use std::io;
 use std::path::PathBuf;
@@ -62,6 +63,11 @@ struct Args {
     #[argh(option, short = 'd', default = r#"PathBuf::from(".")"#)]
     dir: PathBuf,
 
+    /// glob for files to examine; with no glob, all files are examined; globs containing
+    /// slash match the entire path.
+    #[argh(option, short = 'f')]
+    file: Vec<String>,
+
     /// output json (only for --list).
     #[argh(switch)]
     json: bool,
@@ -112,11 +118,11 @@ fn main() -> Result<()> {
         exit(exit_code::USAGE);
     }
     let args: Args = argh::cargo_from_env();
+    let options = Options::try_from(&args)?;
     let source_tree = SourceTree::new(&args.dir)?;
-    let options = Options::from(&args);
     interrupt::install_handler();
     if args.list {
-        let mutants = source_tree.mutants()?;
+        let mutants = source_tree.mutants(&options)?;
         if args.json {
             if args.diff {
                 eprintln!("--list --diff --json is not (yet) supported");

src/options.rs

@@ -2,8 +2,11 @@
 
 //! Global in-process options for experimenting on mutants.
 
+use std::convert::TryFrom;
 use std::time::Duration;
 
+use globset::{Glob, GlobSet, GlobSetBuilder};
+
 use crate::*;
 
 /// Options for running experiments.
@@ -36,6 +39,9 @@ pub struct Options {
 
     /// Build the source directory before copying it.
     pub build_source: bool,
+
+    /// Files to examine.
+    pub globset: Option<GlobSet>,
 }
 
 impl Options {
@@ -55,12 +61,29 @@ impl Options {
     }
 }
 
-impl From<&Args> for Options {
-    fn from(args: &Args) -> Options {
-        Options {
+impl TryFrom<&Args> for Options {
+    type Error = anyhow::Error;
+
+    fn try_from(args: &Args) -> std::result::Result<Options, anyhow::Error> {
+        let globset = if args.file.is_empty() {
+            None
+        } else {
+            let mut builder = GlobSetBuilder::new();
+            for glob_str in &args.file {
+                if glob_str.contains('/') {
+                    builder.add(Glob::new(glob_str)?);
+                } else {
+                    builder.add(Glob::new(&format!("**/{}", glob_str))?);
+                }
+            }
+            Some(builder.build()?)
+        };
+
+        Ok(Options {
             build_source: !args.no_copy_target,
             check_only: args.check,
             copy_target: !args.no_copy_target,
+            globset,
             print_caught: args.caught,
             print_unviable: args.unviable,
             shuffle: !args.no_shuffle,
@@ -71,6 +94,6 @@ impl From<&Args> for Options {
                 .map(Duration::from_secs_f64)
                 .unwrap_or(Duration::MAX),
             additional_cargo_test_args: args.cargo_test_args.clone(),
-        }
+        })
     }
 }

src/source.rs

@@ -72,17 +72,19 @@ impl SourceTree {
     }
 
     /// Return all the mutations that could possibly be applied to this tree.
-    pub fn mutants(&self) -> Result<Vec<Mutant>> {
+    pub fn mutants(&self, options: &Options) -> Result<Vec<Mutant>> {
         let mut r = Vec::new();
-        for sf in self.source_files() {
+        for sf in self.source_files(options) {
             check_interrupted()?;
             r.extend(discover_mutants(sf.into())?);
         }
         Ok(r)
     }
 
     /// Return an iterator of `src/**/*.rs` paths relative to the root.
-    pub fn source_files(&self) -> impl Iterator<Item = SourceFile> + '_ {
+    pub fn source_files(&self, options: &Options) -> impl Iterator<Item = SourceFile> + '_ {
+        let globset = options.globset.clone();
+        let root_path = self.root.clone();
         walkdir::WalkDir::new(self.root.join("src"))
             .sort_by_file_name()
             .into_iter()
@@ -96,6 +98,11 @@ impl SourceTree {
                 path.extension()
                     .map_or(false, |p| p.eq_ignore_ascii_case("rs"))
             })
+            .filter(move |path| {
+                globset.as_ref().map_or(true, |gs| {
+                    gs.is_match(path.strip_prefix(&root_path).expect("strip path prefix"))
+                })
+            })
             .filter_map(move |full_path| {
                 let tree_relative = full_path.strip_prefix(&self.root).unwrap();
                 SourceFile::new(&self.root, tree_relative)
@@ -129,7 +136,7 @@ mod test {
     fn source_files_in_testdata_factorial() {
         let source_paths = SourceTree::new(Path::new("testdata/tree/factorial"))
             .unwrap()
-            .source_files()
+            .source_files(&Options::default())
             .collect::<Vec<SourceFile>>();
         assert_eq!(source_paths.len(), 1);
         assert_eq!(

tests/cli.rs

@@ -164,6 +164,15 @@ fn list_mutants_well_tested() {
         .assert_insta("list_mutants_well_tested");
 }
 
+#[test]
+fn list_mutants_well_tested_name_filter() {
+    run()
+        .arg("mutants")
+        .args(["--list", "--file", "nested_function.rs"])
+        .current_dir("testdata/tree/well_tested")
+        .assert_insta("list_mutants_well_tested_name_filter");
+}
+
 #[test]
 fn list_mutants_json_well_tested() {
     run()

tests/snapshots/cli__list_mutants_well_tested_name_filter.snap

@@ -0,0 +1,8 @@
+---
+source: tests/cli.rs
+assertion_line: 41
+expression: "String::from_utf8_lossy(&output.stdout)"
+---
+src/nested_function.rs:1: replace has_nested -> u32 with Default::default()
+src/nested_function.rs:2: replace has_nested::inner -> u32 with Default::default()
+