Improve ignore-filename-regex heuristic

CHANGELOG.md

@@ -10,6 +10,8 @@ Note: In this file, do not use the hard wrap in the middle of a sentence for com
 
 ## [Unreleased]
 
+- Fix an issue where some files were incorrectly ignored in reports. ([#191](https://github.com/taiki-e/cargo-llvm-cov/pull/191))
+
 ## [0.4.8] - 2022-06-16
 
 - Correctly escape regular expressions passed to `-ignore-filename-regex`. ([#188](https://github.com/taiki-e/cargo-llvm-cov/pull/188), thanks @rhysd)

src/main.rs

@@ -800,12 +800,6 @@ fn ignore_filename_regex(cx: &Context) -> Option<String> {
     #[cfg(windows)]
     const SEPARATOR: &str = "\\\\"; // On windows, we should escape the separator.
 
-    fn default_ignore_filename_regex() -> String {
-        // TODO: Should we use the actual target path instead of using `tests|examples|benches`?
-        //       We may have a directory like tests/support, so maybe we need both?
-        format!(r"(^|{0})(rustc{0}[0-9a-f]+|tests|examples|benches){0}", SEPARATOR)
-    }
-
     #[derive(Default)]
     struct Out(String);
 
@@ -830,20 +824,31 @@ fn ignore_filename_regex(cx: &Context) -> Option<String> {
         out.push(ignore_filename);
     }
     if !cx.cov.disable_default_ignore_filename_regex {
-        out.push(default_ignore_filename_regex());
-        out.push_abs_path(&cx.ws.target_dir);
+        // TODO: Should we use the actual target path instead of using `tests|examples|benches`?
+        //       We may have a directory like tests/support, so maybe we need both?
         if cx.build.remap_path_prefix {
-            for path in [home::home_dir(), home::cargo_home().ok(), home::rustup_home().ok()]
-                .iter()
-                .flatten()
-            {
-                out.push_abs_path(path);
-            }
+            out.push(format!(r"(^|{0})(rustc{0}[0-9a-f]+|tests|examples|benches){0}", SEPARATOR));
         } else {
-            for path in [home::cargo_home().ok(), home::rustup_home().ok()].iter().flatten() {
+            out.push(format!(
+                r"{0}rustc{0}[0-9a-f]+{0}|^{1}({0}.*)?{0}(tests|examples|benches){0}",
+                SEPARATOR,
+                regex::escape(cx.ws.metadata.workspace_root.as_str())
+            ));
+        }
+        out.push_abs_path(&cx.ws.target_dir);
+        if cx.build.remap_path_prefix {
+            if let Some(path) = home::home_dir() {
                 out.push_abs_path(path);
             }
         }
+        if let Ok(path) = home::cargo_home() {
+            let path = regex::escape(path.as_os_str().to_string_lossy().as_ref());
+            let path = format!("^{1}{0}(registry|git){0}", SEPARATOR, path);
+            out.push(path);
+        }
+        if let Ok(path) = home::rustup_home() {
+            out.push_abs_path(path.join("toolchains"));
+        }
         for path in resolve_excluded_paths(cx) {
             out.push_abs_path(path);
         }

tests/fixtures/coverage-reports/real1/all.hide-instantiations.txt

@@ -1,38 +1,42 @@
 member1/member2/src/lib.rs:
-    1|      1|pub fn func(x: u32) {pub fn func(x: u32) {
-    2|      1|    match x {
-    3|      1|        0 => {}
+    1|      2|pub fn func(x: u32) {pub fn func(x: u32) {
+              ^1
+    2|      2|    match x {
+    3|      2|        0 => {}
     4|      0|        1 => {}
     5|      0|        2 => {}
     6|      0|        _ => {}
     7|       |    }
-    8|      1|}
+    8|      2|}
 
 member1/src/lib.rs:
-    1|      1|pub fn func(x: u32) {pub fn func(x: u32) {
-    2|      1|    match x {
-    3|      1|        0 => {}
-    4|      0|        1 => {}
-    5|      0|        2 => {}
-    6|      0|        _ => {}
-    7|       |    }
-    8|      1|}
-
-src/lib.rs:
     1|      2|pub fn func(x: u32) {pub fn func(x: u32) {
               ^1
     2|      2|    match x {
-    3|      0|        0 => {}
-    4|      1|        1 => {}
+    3|      2|        0 => {}
+    4|      0|        1 => {}
     5|      0|        2 => {}
-    6|      1|        _ => {}
+    6|      0|        _ => {}
     7|       |    }
     8|      2|}
-    9|       |
-   10|      1|#[test]
-   11|      1|fn test() {
-   12|      1|    func(1);
-   13|      1|    func(3);
-   14|      1|    member1::func(0);
-   15|      1|    member2::func(0);
-   16|      1|}
+
+src/lib.rs:
+    1|      1|#[cfg(test)]#[cfg(test)]
+    2|       |mod tests;
+    3|       |
+    4|      4|pub fn func(x: u32) {
+    5|      4|    match x {
+    6|      0|        0 => {}
+    7|      2|        1 => {}
+    8|      0|        2 => {}
+    9|      2|        _ => {}
+   10|       |    }
+   11|      4|}
+   12|       |
+   13|      1|#[test]
+   14|      1|fn test() {
+   15|      1|    func(1);
+   16|      1|    func(3);
+   17|      1|    member1::func(0);
+   18|      1|    member2::func(0);
+   19|      1|}

tests/fixtures/coverage-reports/real1/all.txt

@@ -1,64 +1,68 @@
 member1/member2/src/lib.rs:
-    1|      1|pub fn func(x: u32) {pub fn func(x: u32) {
-    2|      1|    match x {
-    3|      1|        0 => {}
+    1|      2|pub fn func(x: u32) {pub fn func(x: u32) {
+              ^1
+    2|      2|    match x {
+    3|      2|        0 => {}
     4|      0|        1 => {}
     5|      0|        2 => {}
     6|      0|        _ => {}
     7|       |    }
-    8|      1|}
+    8|      2|}
   ------------------
   | member2::func:
-  |    1|      1|pub fn func(x: u32) {
-  |    2|      1|    match x {
-  |    3|      1|        0 => {}
+  |    1|      2|pub fn func(x: u32) {
+  |    2|      2|    match x {
+  |    3|      2|        0 => {}
   |    4|      0|        1 => {}
   |    5|      0|        2 => {}
   |    6|      0|        _ => {}
   |    7|       |    }
-  |    8|      1|}
+  |    8|      2|}
   ------------------
   | Unexecuted instantiation: member2::func
   ------------------
 
 member1/src/lib.rs:
-    1|      1|pub fn func(x: u32) {pub fn func(x: u32) {
-    2|      1|    match x {
-    3|      1|        0 => {}
+    1|      2|pub fn func(x: u32) {pub fn func(x: u32) {
+              ^1
+    2|      2|    match x {
+    3|      2|        0 => {}
     4|      0|        1 => {}
     5|      0|        2 => {}
     6|      0|        _ => {}
     7|       |    }
-    8|      1|}
+    8|      2|}
   ------------------
   | member1::func:
-  |    1|      1|pub fn func(x: u32) {
-  |    2|      1|    match x {
-  |    3|      1|        0 => {}
+  |    1|      2|pub fn func(x: u32) {
+  |    2|      2|    match x {
+  |    3|      2|        0 => {}
   |    4|      0|        1 => {}
   |    5|      0|        2 => {}
   |    6|      0|        _ => {}
   |    7|       |    }
-  |    8|      1|}
+  |    8|      2|}
   ------------------
   | Unexecuted instantiation: member1::func
   ------------------
 
 src/lib.rs:
-    1|      2|pub fn func(x: u32) {pub fn func(x: u32) {
-              ^1
-    2|      2|    match x {
-    3|      0|        0 => {}
-    4|      1|        1 => {}
-    5|      0|        2 => {}
-    6|      1|        _ => {}
-    7|       |    }
-    8|      2|}
-    9|       |
-   10|      1|#[test]
-   11|      1|fn test() {
-   12|      1|    func(1);
-   13|      1|    func(3);
-   14|      1|    member1::func(0);
-   15|      1|    member2::func(0);
-   16|      1|}
+    1|      1|#[cfg(test)]#[cfg(test)]
+    2|       |mod tests;
+    3|       |
+    4|      4|pub fn func(x: u32) {
+    5|      4|    match x {
+    6|      0|        0 => {}
+    7|      2|        1 => {}
+    8|      0|        2 => {}
+    9|      2|        _ => {}
+   10|       |    }
+   11|      4|}
+   12|       |
+   13|      1|#[test]
+   14|      1|fn test() {
+   15|      1|    func(1);
+   16|      1|    func(3);
+   17|      1|    member1::func(0);
+   18|      1|    member2::func(0);
+   19|      1|}

tests/fixtures/coverage-reports/real1/workspace_root.hide-instantiations.txt

@@ -1,38 +1,40 @@
 member1/member2/src/lib.rs:
-    1|      1|pub fn func(x: u32) {
-    2|      1|    match x {
-    3|      1|        0 => {}
+    1|      2|pub fn func(x: u32) {
+    2|      2|    match x {
+    3|      2|        0 => {}
     4|      0|        1 => {}
     5|      0|        2 => {}
     6|      0|        _ => {}
     7|       |    }
-    8|      1|}
+    8|      2|}
 
 member1/src/lib.rs:
-    1|      1|pub fn func(x: u32) {
-    2|      1|    match x {
-    3|      1|        0 => {}
+    1|      2|pub fn func(x: u32) {
+    2|      2|    match x {
+    3|      2|        0 => {}
     4|      0|        1 => {}
     5|      0|        2 => {}
     6|      0|        _ => {}
     7|       |    }
-    8|      1|}
+    8|      2|}
 
 src/lib.rs:
-    1|      2|pub fn func(x: u32) {pub fn func(x: u32) {
-              ^1
-    2|      2|    match x {
-    3|      0|        0 => {}
-    4|      1|        1 => {}
-    5|      0|        2 => {}
-    6|      1|        _ => {}
-    7|       |    }
-    8|      2|}
-    9|       |
-   10|      1|#[test]
-   11|      1|fn test() {
-   12|      1|    func(1);
-   13|      1|    func(3);
-   14|      1|    member1::func(0);
-   15|      1|    member2::func(0);
-   16|      1|}
+    1|      1|#[cfg(test)]#[cfg(test)]
+    2|       |mod tests;
+    3|       |
+    4|      4|pub fn func(x: u32) {
+    5|      4|    match x {
+    6|      0|        0 => {}
+    7|      2|        1 => {}
+    8|      0|        2 => {}
+    9|      2|        _ => {}
+   10|       |    }
+   11|      4|}
+   12|       |
+   13|      1|#[test]
+   14|      1|fn test() {
+   15|      1|    func(1);
+   16|      1|    func(3);
+   17|      1|    member1::func(0);
+   18|      1|    member2::func(0);
+   19|      1|}

tests/fixtures/coverage-reports/real1/workspace_root.txt

@@ -1,38 +1,40 @@
 member1/member2/src/lib.rs:
-    1|      1|pub fn func(x: u32) {
-    2|      1|    match x {
-    3|      1|        0 => {}
+    1|      2|pub fn func(x: u32) {
+    2|      2|    match x {
+    3|      2|        0 => {}
     4|      0|        1 => {}
     5|      0|        2 => {}
     6|      0|        _ => {}
     7|       |    }
-    8|      1|}
+    8|      2|}
 
 member1/src/lib.rs:
-    1|      1|pub fn func(x: u32) {
-    2|      1|    match x {
-    3|      1|        0 => {}
+    1|      2|pub fn func(x: u32) {
+    2|      2|    match x {
+    3|      2|        0 => {}
     4|      0|        1 => {}
     5|      0|        2 => {}
     6|      0|        _ => {}
     7|       |    }
-    8|      1|}
+    8|      2|}
 
 src/lib.rs:
-    1|      2|pub fn func(x: u32) {pub fn func(x: u32) {
-              ^1
-    2|      2|    match x {
-    3|      0|        0 => {}
-    4|      1|        1 => {}
-    5|      0|        2 => {}
-    6|      1|        _ => {}
-    7|       |    }
-    8|      2|}
-    9|       |
-   10|      1|#[test]
-   11|      1|fn test() {
-   12|      1|    func(1);
-   13|      1|    func(3);
-   14|      1|    member1::func(0);
-   15|      1|    member2::func(0);
-   16|      1|}
+    1|      1|#[cfg(test)]#[cfg(test)]
+    2|       |mod tests;
+    3|       |
+    4|      4|pub fn func(x: u32) {
+    5|      4|    match x {
+    6|      0|        0 => {}
+    7|      2|        1 => {}
+    8|      0|        2 => {}
+    9|      2|        _ => {}
+   10|       |    }
+   11|      4|}
+   12|       |
+   13|      1|#[test]
+   14|      1|fn test() {
+   15|      1|    func(1);
+   16|      1|    func(3);
+   17|      1|    member1::func(0);
+   18|      1|    member2::func(0);
+   19|      1|}

tests/fixtures/crates/real1/src/lib.rs

@@ -1,3 +1,6 @@
+#[cfg(test)]
+mod tests;
+
 pub fn func(x: u32) {
     match x {
         0 => {}

tests/fixtures/crates/real1/src/tests/mod.rs

@@ -0,0 +1,15 @@
+// src/tests is a well-known pattern: https://grep.app/search?q=%23%5Btest%5D&filter[path][0]=src/tests/&filter[lang][0]=Rust
+//
+// Note that to check that this pattern is properly supported,
+// you need to run cargo-llvm-cov without --remap-path-prefix flag.
+// (Our test suite always enables that flag.)
+
+use super::*;
+
+#[test]
+fn test() {
+    func(1);
+    func(3);
+    member1::func(0);
+    member2::func(0);
+}