fallow_config/config/

resolution.rs

use std::path::{Path, PathBuf};

use globset::{Glob, GlobSet, GlobSetBuilder};
use schemars::JsonSchema;
use serde::{Deserialize, Serialize};

use super::duplicates_config::DuplicatesConfig;
use super::format::OutputFormat;
use super::health::HealthConfig;
use super::rules::{PartialRulesConfig, RulesConfig, Severity};
use crate::external_plugin::{ExternalPluginDef, discover_external_plugins};

use super::FallowConfig;

/// Rule for ignoring specific exports.
#[derive(Debug, Deserialize, Serialize, JsonSchema)]
pub struct IgnoreExportRule {
    /// Glob pattern for files.
    pub file: String,
    /// Export names to ignore (`*` for all).
    pub exports: Vec<String>,
}

/// Per-file override entry.
#[derive(Debug, Clone, Deserialize, Serialize, JsonSchema)]
#[serde(rename_all = "camelCase")]
pub struct ConfigOverride {
    /// Glob patterns to match files against (relative to config file location).
    pub files: Vec<String>,
    /// Partial rules — only specified fields override the base rules.
    #[serde(default)]
    pub rules: PartialRulesConfig,
}

/// Resolved override with pre-compiled glob matchers.
#[derive(Debug)]
pub struct ResolvedOverride {
    pub matchers: Vec<globset::GlobMatcher>,
    pub rules: PartialRulesConfig,
}

/// Fully resolved configuration with all globs pre-compiled.
#[derive(Debug)]
pub struct ResolvedConfig {
    pub root: PathBuf,
    pub entry_patterns: Vec<String>,
    pub ignore_patterns: GlobSet,
    pub output: OutputFormat,
    pub cache_dir: PathBuf,
    pub threads: usize,
    pub no_cache: bool,
    pub ignore_dependencies: Vec<String>,
    pub ignore_export_rules: Vec<IgnoreExportRule>,
    pub duplicates: DuplicatesConfig,
    pub health: HealthConfig,
    pub rules: RulesConfig,
    /// Whether production mode is active.
    pub production: bool,
    /// Suppress progress output and non-essential stderr messages.
    pub quiet: bool,
    /// External plugin definitions (from plugin files + inline framework definitions).
    pub external_plugins: Vec<ExternalPluginDef>,
    /// Per-file rule overrides with pre-compiled glob matchers.
    pub overrides: Vec<ResolvedOverride>,
}

impl FallowConfig {
    /// Resolve into a fully resolved config with compiled globs.
    pub fn resolve(
        self,
        root: PathBuf,
        output: OutputFormat,
        threads: usize,
        no_cache: bool,
        quiet: bool,
    ) -> ResolvedConfig {
        let mut ignore_builder = GlobSetBuilder::new();
        for pattern in &self.ignore_patterns {
            match Glob::new(pattern) {
                Ok(glob) => {
                    ignore_builder.add(glob);
                }
                Err(e) => {
                    tracing::warn!("invalid ignore glob pattern '{pattern}': {e}");
                }
            }
        }

        // Default ignores
        // Note: `build/` is only ignored at the project root (not `**/build/**`)
        // because nested `build/` directories like `test/build/` may contain source files.
        let default_ignores = [
            "**/node_modules/**",
            "**/dist/**",
            "build/**",
            "**/.git/**",
            "**/coverage/**",
            "**/*.min.js",
            "**/*.min.mjs",
        ];
        for pattern in &default_ignores {
            if let Ok(glob) = Glob::new(pattern) {
                ignore_builder.add(glob);
            }
        }

        let compiled_ignore_patterns = ignore_builder.build().unwrap_or_default();
        let cache_dir = root.join(".fallow");

        let mut rules = self.rules;

        // In production mode, force unused_dev_dependencies and unused_optional_dependencies off
        let production = self.production;
        if production {
            rules.unused_dev_dependencies = Severity::Off;
            rules.unused_optional_dependencies = Severity::Off;
        }

        let mut external_plugins = discover_external_plugins(&root, &self.plugins);
        // Merge inline framework definitions into external plugins
        external_plugins.extend(self.framework);

        // Pre-compile override glob matchers
        let overrides = self
            .overrides
            .into_iter()
            .filter_map(|o| {
                let matchers: Vec<globset::GlobMatcher> = o
                    .files
                    .iter()
                    .filter_map(|pattern| match Glob::new(pattern) {
                        Ok(glob) => Some(glob.compile_matcher()),
                        Err(e) => {
                            tracing::warn!("invalid override glob pattern '{pattern}': {e}");
                            None
                        }
                    })
                    .collect();
                if matchers.is_empty() {
                    None
                } else {
                    Some(ResolvedOverride {
                        matchers,
                        rules: o.rules,
                    })
                }
            })
            .collect();

        ResolvedConfig {
            root,
            entry_patterns: self.entry,
            ignore_patterns: compiled_ignore_patterns,
            output,
            cache_dir,
            threads,
            no_cache,
            ignore_dependencies: self.ignore_dependencies,
            ignore_export_rules: self.ignore_exports,
            duplicates: self.duplicates,
            health: self.health,
            rules,
            production,
            quiet,
            external_plugins,
            overrides,
        }
    }
}

impl ResolvedConfig {
    /// Resolve the effective rules for a given file path.
    /// Starts with base rules and applies matching overrides in order.
    pub fn resolve_rules_for_path(&self, path: &Path) -> RulesConfig {
        if self.overrides.is_empty() {
            return self.rules.clone();
        }

        let relative = path.strip_prefix(&self.root).unwrap_or(path);
        let relative_str = relative.to_string_lossy();

        let mut rules = self.rules.clone();
        for override_entry in &self.overrides {
            let matches = override_entry
                .matchers
                .iter()
                .any(|m| m.is_match(relative_str.as_ref()));
            if matches {
                rules.apply_partial(&override_entry.rules);
            }
        }
        rules
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::config::health::HealthConfig;

    #[test]
    fn overrides_deserialize() {
        let json_str = r#"{
            "overrides": [{
                "files": ["*.test.ts"],
                "rules": {
                    "unused-exports": "off"
                }
            }]
        }"#;
        let config: FallowConfig = serde_json::from_str(json_str).unwrap();
        assert_eq!(config.overrides.len(), 1);
        assert_eq!(config.overrides[0].files, vec!["*.test.ts"]);
        assert_eq!(
            config.overrides[0].rules.unused_exports,
            Some(Severity::Off)
        );
        assert_eq!(config.overrides[0].rules.unused_files, None);
    }

    #[test]
    fn resolve_rules_for_path_no_overrides() {
        let config = FallowConfig {
            schema: None,
            extends: vec![],
            entry: vec![],
            ignore_patterns: vec![],
            framework: vec![],
            workspaces: None,
            ignore_dependencies: vec![],
            ignore_exports: vec![],
            duplicates: DuplicatesConfig::default(),
            health: HealthConfig::default(),
            rules: RulesConfig::default(),
            production: false,
            plugins: vec![],
            overrides: vec![],
        };
        let resolved = config.resolve(
            PathBuf::from("/project"),
            OutputFormat::Human,
            1,
            true,
            true,
        );
        let rules = resolved.resolve_rules_for_path(Path::new("/project/src/foo.ts"));
        assert_eq!(rules.unused_files, Severity::Error);
    }

    #[test]
    fn resolve_rules_for_path_with_matching_override() {
        let config = FallowConfig {
            schema: None,
            extends: vec![],
            entry: vec![],
            ignore_patterns: vec![],
            framework: vec![],
            workspaces: None,
            ignore_dependencies: vec![],
            ignore_exports: vec![],
            duplicates: DuplicatesConfig::default(),
            health: HealthConfig::default(),
            rules: RulesConfig::default(),
            production: false,
            plugins: vec![],
            overrides: vec![ConfigOverride {
                files: vec!["*.test.ts".to_string()],
                rules: PartialRulesConfig {
                    unused_exports: Some(Severity::Off),
                    ..Default::default()
                },
            }],
        };
        let resolved = config.resolve(
            PathBuf::from("/project"),
            OutputFormat::Human,
            1,
            true,
            true,
        );

        // Test file matches override
        let test_rules = resolved.resolve_rules_for_path(Path::new("/project/src/utils.test.ts"));
        assert_eq!(test_rules.unused_exports, Severity::Off);
        assert_eq!(test_rules.unused_files, Severity::Error); // not overridden

        // Non-test file does not match
        let src_rules = resolved.resolve_rules_for_path(Path::new("/project/src/utils.ts"));
        assert_eq!(src_rules.unused_exports, Severity::Error);
    }

    #[test]
    fn resolve_rules_for_path_later_override_wins() {
        let config = FallowConfig {
            schema: None,
            extends: vec![],
            entry: vec![],
            ignore_patterns: vec![],
            framework: vec![],
            workspaces: None,
            ignore_dependencies: vec![],
            ignore_exports: vec![],
            duplicates: DuplicatesConfig::default(),
            health: HealthConfig::default(),
            rules: RulesConfig::default(),
            production: false,
            plugins: vec![],
            overrides: vec![
                ConfigOverride {
                    files: vec!["*.ts".to_string()],
                    rules: PartialRulesConfig {
                        unused_files: Some(Severity::Warn),
                        ..Default::default()
                    },
                },
                ConfigOverride {
                    files: vec!["*.test.ts".to_string()],
                    rules: PartialRulesConfig {
                        unused_files: Some(Severity::Off),
                        ..Default::default()
                    },
                },
            ],
        };
        let resolved = config.resolve(
            PathBuf::from("/project"),
            OutputFormat::Human,
            1,
            true,
            true,
        );

        // First override matches *.ts, second matches *.test.ts; second wins
        let rules = resolved.resolve_rules_for_path(Path::new("/project/foo.test.ts"));
        assert_eq!(rules.unused_files, Severity::Off);

        // Non-test .ts file only matches first override
        let rules2 = resolved.resolve_rules_for_path(Path::new("/project/foo.ts"));
        assert_eq!(rules2.unused_files, Severity::Warn);
    }
}