Support for test-file exclusions (#96)

Exclude test files with the new `testFilePatterns` config option.

Files matching these globs will be treated as used and tagged as test
files, as well as the transitive imports of files matching these globs.

change/@good-fences-api-67c8e574-b15f-4542-a781-4b625f530df0.json

@@ -0,0 +1,7 @@
+{
+  "type": "minor",
+  "comment": "Add support for usage from test files",
+  "packageName": "@good-fences/api",
+  "email": "mhuan13@gmail.com",
+  "dependentChangeType": "patch"
+}

crates/unused_finder/src/cfg/mod.rs

@@ -3,7 +3,7 @@ use std::fmt::{Display, Formatter};
 use package_match_rules::PackageMatchRules;
 use serde::Deserialize;
 
-mod package_match_rules;
+pub mod package_match_rules;
 
 #[derive(Debug, Eq, PartialEq)]
 pub struct ErrList<E>(Vec<E>);
@@ -89,11 +89,25 @@ pub struct UnusedFinderJSONConfig {
     /// All transitive imports from the exposed exports of these packages
     /// will be considered used
     ///
+    /// Note that the only files that are considered roots are the ones
+    /// that are _explicitly exported_, either as an entry in the package's "exports" config,
+    /// or as a main/module export
+    ///
     /// Items are parsed in one of three ways:
-    /// 1. If the item starts with "./", it is treated as a path glob, and evaluated against the paths of package folders, relative to the repo root.
-    /// 2. If the item contains any of "~)('!*", it is treated as a name-glob, and evaluated as a glob against the names of packages.
-    /// 3. Otherwise, the item is treated as the name of an individual package, and matched literally.
+    /// 1. If the item starts with "./", it is treated as a path glob, and evaluated
+    ///    against the paths of package folders, relative to the repo root.
+    /// 2. If the item contains any of "~)('!*", it is treated as a name-glob, and evaluated
+    ///    as a glob against the names of packages.
+    /// 3. Otherwise, the item is treated as the name of an individual package, and matched
+    ///    literally.
     pub entry_packages: Vec<String>,
+    /// List of globs that will be matched against files in the repository
+    ///
+    /// Matches are made against the relative file paths from the repo root.
+    /// A matching file will be tagged as a "test" file, and will be excluded
+    /// from the list of unused files
+    #[serde(default)]
+    pub test_file_patterns: Vec<String>,
 }
 
 /// Configuration for the unused symbols finder
@@ -115,6 +129,13 @@ pub struct UnusedFinderConfig {
     /// packages we should consider as "entry" packages
     pub entry_packages: PackageMatchRules,
 
+    /// List of globs that will be matched against files in the repository
+    ///
+    /// Matches are made against the relative file paths from the repo root.
+    /// A matching file will be tagged as a "test" file, and will be excluded
+    /// from the list of unused files
+    pub test_file_patterns: Vec<glob::Pattern>,
+
     /// Globs of individual files & directories to skip during the file walk.
     ///
     /// Some internal directories are always skipped.
@@ -133,6 +154,14 @@ impl TryFrom<UnusedFinderJSONConfig> for UnusedFinderConfig {
             repo_root: value.repo_root,
             // other fields that are processed before use
             entry_packages: value.entry_packages.try_into()?,
+            test_file_patterns: value
+                .test_file_patterns
+                .iter()
+                .map(|p| glob::Pattern::new(p))
+                .collect::<Result<_, _>>()
+                .map_err(|e| {
+                    ConfigError::InvalidGlobPatterns(ErrList(vec![PatErr(0, GlobInterp::Path, e)]))
+                })?,
             skip: value.skip,
         })
     }

crates/unused_finder/src/cfg/package_match_rules.rs

@@ -44,6 +44,12 @@ impl PackageMatchRules {
     }
 }
 
+impl PackageMatchRules {
+    pub fn empty() -> Self {
+        Self::default()
+    }
+}
+
 impl<T: AsRef<str> + ToString> TryFrom<Vec<T>> for PackageMatchRules {
     type Error = ConfigError;
     fn try_from(value: Vec<T>) -> Result<Self, Self::Error> {

crates/unused_finder/src/test.rs

@@ -1,11 +1,11 @@
-use std::{collections::HashMap, path::PathBuf};
+use std::{collections::HashMap, path::PathBuf, str::FromStr};
 
 use path_slash::PathBufExt;
 use test_tmpdir::{bmap, test_tmpdir};
 
 use crate::{
-    graph::UsedTag, logger, report::SymbolReport, UnusedFinder, UnusedFinderConfig,
-    UnusedFinderReport,
+    cfg::package_match_rules::PackageMatchRules, graph::UsedTag, logger, report::SymbolReport,
+    UnusedFinder, UnusedFinderConfig, UnusedFinderReport,
 };
 
 fn symbol(id: &str, tags: UsedTag) -> SymbolReport {
@@ -409,3 +409,44 @@ fn test_typeonly_interface_allowed() {
         },
     );
 }
+
+#[test]
+fn test_testfiles_ignored() {
+    // Tests that test files are ignored
+    let tmpdir = test_tmpdir!(
+        "search_root/packages/__tests__/myTests.test.js" => r#"
+            import { myFunction } from "../test-helpers/test-helpers";
+        "#,
+        "search_root/packages/test-helpers/package.json" => r#"{
+            "name": "test-helpers",
+            "exports": {
+                "." : {
+                    "source": "./test-helpers.js"
+                }
+            }
+        }"#,
+        "search_root/packages/test-helpers/test-helpers.js" => r#"
+            export function myFunction() {}
+        "#,
+        "search_root/packages/test-helpers/unused-helpers.js" => r#"
+            export function myFunction() {}
+        "#
+    );
+
+    run_unused_test(
+        &tmpdir,
+        UnusedFinderConfig {
+            repo_root: tmpdir.root().to_string_lossy().to_string(),
+            root_paths: vec!["search_root".to_string()],
+            entry_packages: PackageMatchRules::empty(),
+            test_file_patterns: vec![glob::Pattern::from_str("**/__tests__/**").unwrap()],
+            ..Default::default()
+        },
+        UnusedFinderReport {
+            unused_files: vec!["<root>/search_root/packages/test-helpers/unused-helpers.js".into()],
+            unused_symbols: bmap![
+                "<root>/search_root/packages/test-helpers/unused-helpers.js" => vec![symbol("myFunction", UsedTag::default())]
+            ],
+        },
+    );
+}

crates/unused_finder/src/unused_finder.rs

@@ -352,6 +352,16 @@ impl UnusedFinder {
             )
             .map_err(JsErr::generic_failure)?;
 
+        let test_entrypoints = self.get_test_files();
+        logger.log(format!(
+            "Starting {} graph traversal with {} entrypoints",
+            UsedTag::FROM_TEST,
+            test_entrypoints.len(),
+        ));
+        graph
+            .traverse_bfs(&logger, test_entrypoints, vec![], UsedTag::FROM_TEST)
+            .map_err(JsErr::generic_failure)?;
+
         // mark all typeonly symbols
         if self.config.allow_unused_types {
             for (path, source_file) in self.last_walk_result.source_files.iter() {
@@ -445,6 +455,26 @@ impl UnusedFinder {
             .unwrap_or(false)
     }
 
+    fn get_test_files(&self) -> Vec<PathBuf> {
+        // get the list of files that match the test file patterns
+        self.last_walk_result
+            .source_files
+            .par_iter()
+            .filter_map(|(file_path, _)| {
+                if self
+                    .config
+                    .test_file_patterns
+                    .iter()
+                    .any(|pattern| pattern.matches_path(file_path))
+                {
+                    Some(file_path.clone())
+                } else {
+                    None
+                }
+            })
+            .collect()
+    }
+
     fn get_ignored_files(&self) -> Vec<PathBuf> {
         // TODO: this is n^2, which is bad! Could build a treemap of ignore files?
         self.last_walk_result

crates/unused_finder_napi/src/lib.rs

@@ -49,6 +49,13 @@ pub struct UnusedFinderJSONConfig {
     /// 2. If the item contains any of "~)('!*", it is treated as a name-glob, and evaluated as a glob against the names of packages.
     /// 3. Otherwise, the item is treated as the name of an individual package, and matched literally.
     pub entry_packages: Vec<String>,
+    /// List of globs that will be matched against files in the repository
+    ///
+    /// Matches are made against the relative file paths from the repo root.
+    /// A matching file will be tagged as a "test" file, and will be excluded
+    /// from the list of unused files
+    #[serde(default)]
+    pub test_file_patterns: Vec<String>,
 }
 
 impl From<UnusedFinderJSONConfig> for unused_finder::UnusedFinderJSONConfig {
@@ -60,6 +67,7 @@ impl From<UnusedFinderJSONConfig> for unused_finder::UnusedFinderJSONConfig {
             report_exported_symbols: val.report_exported_symbols,
             entry_packages: val.entry_packages,
             allow_unused_types: val.allow_unused_types,
+            test_file_patterns: val.test_file_patterns,
         }
     }
 }