feat(migrate): add migrate eslint (#2103)

CHANGELOG.md

@@ -21,8 +21,84 @@ our [guidelines for writing a good changelog entry](https://github.com/biomejs/b
 
 #### New features
 
+- Add a command to migrate from ESLint
+
+  `@biomejs/biome migrate eslint` allows you to migrate an ESLint configuration to Biome.
+  The command supports [legacy ESLint configurations](https://eslint.org/docs/latest/use/configure/configuration-files) and [new flat ESLint configurations](https://eslint.org/docs/latest/use/configure/configuration-files-new).
+  Legacy ESLint configurations using the YAML format are not supported.
+
+  When loading a legacy ESLint configuration, Biome resolves the `extends` field.
+  It resolves both shared configurations and plugin presets!
+  To do this, it invokes NodeJS.
+
+  Biome relies on the metadata of its rules to determine the [equivalent rule of an ESLint rule](https://biomejs.dev/linter/rules-sources/).
+  A Biome rule is either inspired or roughly identical to an ESLint rules.
+  By default, inspired and nursery rules are excluded from the migration.
+  You can use the CLI flags `--include-inspired` and `--include-nursery` to migrate them as well.
+
+  Note that this is a best-effort approach.
+  You are not guaranteed to get the same behavior as ESLint.
+
+  Given the following ESLint configuration:
+
+  ```json
+  {
+        "ignore_patterns": ["**/*.test.js"],
+        "globals": { "var2": "readonly" },
+        "rules": {
+            "eqeqeq": "error"
+        },
+        "overrides": [{
+            "files": ["lib/*.js"],
+            "rules": {
+              "default-param-last": "off"
+            }
+        }]
+  }
+  ```
+
+  `@biomejs/biome migrate eslint --write` changes the Biome configuration as follows:
+
+  ```json
+  {
+    "linter": {
+      "rules": {
+        "recommended": false,
+        "suspicious": {
+          "noDoubleEquals": "error"
+        }
+      }
+    },
+    "javascript": { "globals": ["var2"] },
+    "overrides": [{
+      "include": ["lib/*.js"],
+      "linter": {
+        "rules": {
+          "style": {
+            "useDefaultParameterLast": "off"
+          }
+        }
+      }
+    }]
+  }
+  ```
+
+  Also, if the working diretcory contains `.eslintignore`, then Biome migrates the glob patterns.
+  Nested `.eslintignore` in subdirectories and negated glob patterns are not supported.
+
+  If you find any issue, please don't hesitate to report them.
+
+  Contributed by @Conaclos
+
 #### Enhancements
 
+- Improve support of `.prettierignore` when migrating from Prettier
+
+  Now, Biome translates most of the glob patterns in `.prettierignore` to the equivalent Biome ignore pattern.
+  Only negated glob patterns are not supported.
+
+  Contributed by @Conaclos
+
 ### Configuration
 
 #### Enhancements
@@ -714,7 +790,7 @@ Additionally, the following rules are now recommended:
 
   ```diff
   - <div class="px-2 foo p-4 bar" />
-  + <div class="foo·bar·p-4·px-2" />
+  + <div class="foo bar p-4 px-2" />
   ```
   Contributed by @DaniGuardiola
 
@@ -936,7 +1012,7 @@ Additionally, the following rules are now recommended:
 - Fix [#1656](https://github.com/biomejs/biome/issues/1656). [useOptionalChain](https://biomejs.dev/linter/rules/use-optional-chain/) code action now correctly handles logical and chains where methods with the same name are invoked with different arguments:
 
   ```diff
-  - tags·&&·tags.includes('a')·&&·tags.includes('b')
+  - tags && tags.includes('a') && tags.includes('b')
   + tags?.includes('a') && tags.includes('b')
   ```
 

crates/biome_analyze/src/rule.rs

@@ -158,6 +158,24 @@ impl RuleSource {
         }
     }
 
+    pub fn to_namespaced_rule_name(&self) -> String {
+        match self {
+            Self::Clippy(rule_name) | Self::Eslint(rule_name) => (*rule_name).to_string(),
+            Self::EslintImport(rule_name) => format!("import/{rule_name}"),
+            Self::EslintImportAccess(rule_name) => format!("import-access/{rule_name}"),
+            Self::EslintJest(rule_name) => format!("jest/{rule_name}"),
+            Self::EslintJsxA11y(rule_name) => format!("jsx-a11y/{rule_name}"),
+            Self::EslintReact(rule_name) => format!("react/{rule_name}"),
+            Self::EslintReactHooks(rule_name) => format!("react-hooks/{rule_name}"),
+            Self::EslintTypeScript(rule_name) => format!("@typescript-eslint/{rule_name}"),
+            Self::EslintSonarJs(rule_name) => format!("sonarjs/{rule_name}"),
+            Self::EslintStylistic(rule_name) => format!("@stylistic/{rule_name}"),
+            Self::EslintUnicorn(rule_name) => format!("unicorn/{rule_name}"),
+            Self::EslintMysticatea(rule_name) => format!("@mysticatea/{rule_name}"),
+            Self::EslintBarrelFiles(rule_name) => format!("barrel-files/{rule_name}"),
+        }
+    }
+
     pub fn to_rule_url(&self) -> String {
         match self {
             Self::Clippy(rule_name) => format!("https://rust-lang.github.io/rust-clippy/master/#/{rule_name}"),
@@ -186,29 +204,9 @@ impl RuleSource {
         matches!(self, Self::Eslint(_))
     }
 
-    /// TypeScript plugin
-    pub const fn is_eslint_typescript(&self) -> bool {
-        matches!(self, Self::EslintTypeScript(_))
-    }
-
     /// All ESLint plugins, exception for the TypeScript one
     pub const fn is_eslint_plugin(&self) -> bool {
-        matches!(
-            self,
-            Self::EslintImport(_)
-                | Self::EslintImportAccess(_)
-                | Self::EslintJest(_)
-                | Self::EslintStylistic(_)
-                | Self::EslintJsxA11y(_)
-                | Self::EslintReact(_)
-                | Self::EslintReactHooks(_)
-                | Self::EslintSonarJs(_)
-                | Self::EslintUnicorn(_)
-        )
-    }
-
-    pub const fn is_clippy(&self) -> bool {
-        matches!(self, Self::Clippy(_))
+        !matches!(self, Self::Clippy(_) | Self::Eslint(_))
     }
 }
 

crates/biome_cli/Cargo.toml

@@ -27,6 +27,7 @@ biome_deserialize_macros = { workspace = true }
 biome_diagnostics        = { workspace = true }
 biome_formatter          = { workspace = true }
 biome_fs                 = { workspace = true }
+biome_js_analyze         = { workspace = true }
 biome_js_formatter       = { workspace = true }
 biome_json_formatter     = { workspace = true }
 biome_json_parser        = { workspace = true }
@@ -46,6 +47,7 @@ rayon                    = { workspace = true }
 rustc-hash               = { workspace = true }
 serde                    = { workspace = true, features = ["derive"] }
 serde_json               = { workspace = true }
+smallvec                 = { workspace = true }
 tokio                    = { workspace = true, features = ["io-std", "io-util", "net", "time", "rt", "sync", "rt-multi-thread", "macros"] }
 tracing                  = { workspace = true }
 tracing-appender         = "0.2"

crates/biome_cli/src/commands/migrate.rs

@@ -2,21 +2,19 @@ use crate::cli_options::CliOptions;
 use crate::diagnostics::MigrationDiagnostic;
 use crate::execute::{execute_mode, Execution, TraversalMode};
 use crate::{setup_cli_subscriber, CliDiagnostic, CliSession};
-use biome_configuration::ConfigurationBasePath;
+use biome_console::{markup, ConsoleExt};
 use biome_service::configuration::{load_configuration, LoadedConfiguration};
-use std::path::PathBuf;
+
+use super::MigrateSubCommand;
 
 /// Handler for the "check" command of the Biome CLI
 pub(crate) fn migrate(
     session: CliSession,
     cli_options: CliOptions,
     write: bool,
-    prettier: bool,
+    sub_command: Option<MigrateSubCommand>,
 ) -> Result<(), CliDiagnostic> {
-    let base_path = match cli_options.config_path.as_ref() {
-        None => ConfigurationBasePath::default(),
-        Some(path) => ConfigurationBasePath::FromUser(PathBuf::from(path)),
-    };
+    let base_path = cli_options.as_configuration_base_path();
     let LoadedConfiguration {
         configuration: _,
         diagnostics: _,
@@ -31,15 +29,19 @@ pub(crate) fn migrate(
                 write,
                 configuration_file_path: path,
                 configuration_directory_path: directory_path,
-                prettier,
+                sub_command,
             }),
             session,
             &cli_options,
             vec![],
         )
     } else {
+        let console = session.app.console;
+        console.log(markup! {
+            <Info>"If this project has not yet been set up with Biome yet, please follow the "<Hyperlink href="https://biomejs.dev/guides/getting-started/">"Getting Started guide"</Hyperlink>" first."</Info>
+        });
         Err(CliDiagnostic::MigrateError(MigrationDiagnostic {
-            reason: "Biome couldn't find the configuration file".to_string(),
+            reason: "Biome couldn't find the Biome configuration file.".to_string(),
         }))
     }
 }

crates/biome_cli/src/commands/mod.rs

@@ -346,6 +346,16 @@ pub enum MigrateSubCommand {
     /// It attempts to find the files `.prettierrc`/`prettier.json` and `.prettierignore`, and map the Prettier's configuration into Biome's configuration file.
     #[bpaf(command)]
     Prettier,
+    /// It attempts to find the ESLint configuration file in the working directory, and update the Biome's configuration file as a result.
+    #[bpaf(command)]
+    Eslint {
+        /// Includes rules inspired from an eslint rule in the migration
+        #[bpaf(long("include-inspired"))]
+        include_inspired: bool,
+        /// Includes nursery rules in the migration
+        #[bpaf(long("include-nursery"))]
+        include_nursery: bool,
+    },
 }
 
 impl MigrateSubCommand {