Add lint groups to Q#

compiler/qsc/src/interpret.rs

@@ -404,10 +404,12 @@ impl Interpreter {
                 compile_unit,
                 // see https://github.com/microsoft/qsharp/pull/1627 for context
                 // on why we override this config
-                Some(&[qsc_linter::LintConfig {
-                    kind: LintKind::Hir(HirLint::NeedlessOperation),
-                    level: LintLevel::Warn,
-                }]),
+                Some(&[qsc_linter::LintOrGroupConfig::Lint(
+                    qsc_linter::LintConfig {
+                        kind: LintKind::Hir(HirLint::NeedlessOperation),
+                        level: LintLevel::Warn,
+                    },
+                )]),
             )
         } else {
             Vec::new()

compiler/qsc/src/lib.rs

@@ -58,7 +58,9 @@ pub use qsc_eval::{
 };
 
 pub mod linter {
-    pub use qsc_linter::{run_lints, LintConfig, LintKind, LintLevel};
+    pub use qsc_linter::{
+        run_lints, GroupConfig, LintConfig, LintKind, LintLevel, LintOrGroupConfig,
+    };
 }
 
 pub use qsc_doc_gen::{display, generate_docs};

compiler/qsc_linter/Cargo.toml

@@ -15,6 +15,7 @@ qsc_hir = { path = "../qsc_hir" }
 qsc_data_structures = { path = "../qsc_data_structures" }
 qsc_frontend = { path = "../qsc_frontend" }
 qsc_doc_gen = { path = "../qsc_doc_gen" }
+rustc-hash = { workspace = true }
 serde = { workspace = true }
 thiserror = { workspace = true }
 

compiler/qsc_linter/src/lib.rs

@@ -61,10 +61,12 @@
 
 #![deny(missing_docs)]
 
+mod lint_groups;
 mod linter;
 mod lints;
 #[cfg(test)]
 mod tests;
 
-pub use linter::{run_lints, Lint, LintConfig, LintKind, LintLevel};
+pub use lint_groups::GroupConfig;
+pub use linter::{run_lints, Lint, LintConfig, LintKind, LintLevel, LintOrGroupConfig};
 pub use lints::{ast::AstLint, hir::HirLint};

compiler/qsc_linter/src/lint_groups.rs

@@ -0,0 +1,42 @@
+use serde::{Deserialize, Serialize};
+
+use crate::{LintKind, LintLevel};
+
+/// End-user configuration for a lint group.
+#[derive(Debug, Clone, Deserialize, Serialize, PartialEq, Eq)]
+pub struct GroupConfig {
+    #[serde(rename = "group")]
+    /// The lint group.
+    pub lint_group: LintGroup,
+    /// The group level.
+    pub level: LintLevel,
+}
+
+#[derive(Debug, Clone, Copy, Deserialize, Serialize, PartialEq, Eq)]
+#[serde(rename_all = "camelCase")]
+pub enum LintGroup {
+    Pedantic,
+}
+
+impl LintGroup {
+    pub fn unfold(self) -> Vec<LintKind> {
+        use crate::AstLint::*;
+        use crate::HirLint::*;
+        match self {
+            LintGroup::Pedantic => {
+                vec![
+                    LintKind::Ast(DivisionByZero),
+                    LintKind::Ast(NeedlessParens),
+                    LintKind::Ast(RedundantSemicolons),
+                    LintKind::Ast(DeprecatedNewtype),
+                    LintKind::Ast(DeprecatedSet),
+                    LintKind::Ast(DiscourageChainAssignment),
+                    LintKind::Hir(NeedlessOperation),
+                    LintKind::Hir(DeprecatedFunctionConstructor),
+                    LintKind::Hir(DeprecatedWithOperator),
+                    LintKind::Hir(DeprecatedDoubleColonOperator),
+                ]
+            }
+        }
+    }
+}

compiler/qsc_linter/src/linter.rs

@@ -5,11 +5,15 @@ pub(crate) mod ast;
 pub(crate) mod hir;
 
 use self::{ast::run_ast_lints, hir::run_hir_lints};
-use crate::lints::{ast::AstLint, hir::HirLint};
+use crate::{
+    lints::{ast::AstLint, hir::HirLint},
+    GroupConfig,
+};
 use miette::{Diagnostic, LabeledSpan};
 use qsc_data_structures::span::Span;
 use qsc_frontend::compile::{CompileUnit, PackageStore};
 use qsc_hir::hir::{Item, ItemId};
+use rustc_hash::FxHashMap;
 use serde::{Deserialize, Serialize};
 use std::fmt::Display;
 
@@ -19,22 +23,61 @@ use std::fmt::Display;
 pub fn run_lints(
     package_store: &PackageStore,
     compile_unit: &CompileUnit,
-    config: Option<&[LintConfig]>,
+    config: Option<&[LintOrGroupConfig]>,
 ) -> Vec<Lint> {
     let compilation = Compilation {
         package_store,
         compile_unit,
     };
 
-    let mut ast_lints = run_ast_lints(&compile_unit.ast.package, config, compilation);
-    let mut hir_lints = run_hir_lints(&compile_unit.package, config, compilation);
+    let unfolded_config = config.map(unfold_groups);
+
+    let mut ast_lints = run_ast_lints(
+        &compile_unit.ast.package,
+        unfolded_config.as_deref(),
+        compilation,
+    );
+    let mut hir_lints = run_hir_lints(
+        &compile_unit.package,
+        unfolded_config.as_deref(),
+        compilation,
+    );
 
     let mut lints = Vec::new();
     lints.append(&mut ast_lints);
     lints.append(&mut hir_lints);
     lints
 }
 
+/// Unfolds groups into lists of lints. Specific lints override group configs.
+pub(crate) fn unfold_groups(config: &[LintOrGroupConfig]) -> Vec<LintConfig> {
+    let mut config_map: FxHashMap<LintKind, LintLevel> = FxHashMap::default();
+
+    // Unfold groups in the order they appear.
+    for elt in config {
+        if let LintOrGroupConfig::Group(group) = elt {
+            for lint in group.lint_group.unfold() {
+                config_map.insert(lint, group.level);
+            }
+        }
+    }
+
+    // Specific lints override group configs.
+    for elt in config {
+        if let LintOrGroupConfig::Lint(lint) = elt {
+            config_map.insert(lint.kind, lint.level);
+        }
+    }
+
+    config_map
+        .iter()
+        .map(|(kind, level)| LintConfig {
+            kind: *kind,
+            level: *level,
+        })
+        .collect()
+}
+
 #[derive(Clone, Copy)]
 pub(crate) struct Compilation<'a> {
     pub package_store: &'a PackageStore,
@@ -177,18 +220,28 @@ impl Display for LintLevel {
     }
 }
 
-/// End-user configuration for each lint level.
+/// End-user configuration for a specific lint or a lint group.
+#[derive(Debug, Clone, Deserialize, Serialize, PartialEq, Eq)]
+#[serde(untagged)]
+pub enum LintOrGroupConfig {
+    /// An specific lint configuration.
+    Lint(LintConfig),
+    /// A lint group configuration.
+    Group(GroupConfig),
+}
+
+/// End-user configuration for a specific lint.
 #[derive(Debug, Clone, Deserialize, Serialize, PartialEq, Eq)]
 pub struct LintConfig {
     #[serde(rename = "lint")]
-    /// Represents the lint name.
+    /// The lint name.
     pub kind: LintKind,
     /// The lint level.
     pub level: LintLevel,
 }
 
 /// Represents a lint name.
-#[derive(Debug, Clone, Copy, Deserialize, Serialize, PartialEq, Eq)]
+#[derive(Debug, Clone, Copy, Deserialize, Serialize, PartialEq, Eq, Hash)]
 #[serde(untagged)]
 pub enum LintKind {
     /// AST lint name.

compiler/qsc_linter/src/linter/ast.rs

@@ -3,7 +3,7 @@
 
 use crate::{
     lints::ast::{AstLint, CombinedAstLints},
-    Lint, LintConfig, LintLevel,
+    Lint, LintLevel,
 };
 use qsc_ast::{
     ast::{
@@ -24,9 +24,9 @@ pub fn run_ast_lints(
     let config: Vec<(AstLint, LintLevel)> = config
         .unwrap_or(&[])
         .iter()
-        .filter_map(|lint_config| {
-            if let LintKind::Ast(kind) = lint_config.kind {
-                Some((kind, lint_config.level))
+        .filter_map(|lint| {
+            if let LintKind::Ast(kind) = lint.kind {
+                Some((kind, lint.level))
             } else {
                 None
             }
@@ -185,7 +185,7 @@ macro_rules! declare_ast_lints {
         use serde::{Deserialize, Serialize};
 
         /// An enum listing all existing AST lints.
-        #[derive(Debug, Clone, Copy, Deserialize, Serialize, PartialEq, Eq)]
+        #[derive(Debug, Clone, Copy, Deserialize, Serialize, PartialEq, Eq, Hash)]
         #[serde(rename_all = "camelCase")]
         pub enum AstLint {
             $(
@@ -342,4 +342,4 @@ macro_rules! declare_ast_lints {
 
 pub(crate) use declare_ast_lints;
 
-use super::{Compilation, LintKind};
+use super::{Compilation, LintConfig, LintKind};

compiler/qsc_linter/src/linter/hir.rs

@@ -3,7 +3,7 @@
 
 use crate::{
     lints::hir::{CombinedHirLints, HirLint},
-    Lint, LintConfig, LintLevel,
+    Lint, LintLevel,
 };
 use qsc_hir::{
     hir::{Block, CallableDecl, Expr, Ident, Item, Package, Pat, QubitInit, SpecDecl, Stmt},
@@ -21,9 +21,9 @@ pub fn run_hir_lints(
     let config: Vec<(HirLint, LintLevel)> = config
         .unwrap_or(&[])
         .iter()
-        .filter_map(|lint_config| {
-            if let LintKind::Hir(kind) = lint_config.kind {
-                Some((kind, lint_config.level))
+        .filter_map(|lint| {
+            if let LintKind::Hir(kind) = lint.kind {
+                Some((kind, lint.level))
             } else {
                 None
             }
@@ -149,7 +149,7 @@ macro_rules! declare_hir_lints {
         use serde::{Deserialize, Serialize};
 
         /// An enum listing all existing HIR lints.
-        #[derive(Debug, Clone, Copy, Deserialize, Serialize, PartialEq, Eq)]
+        #[derive(Debug, Clone, Copy, Deserialize, Serialize, PartialEq, Eq, Hash)]
         #[serde(rename_all = "camelCase")]
         pub enum HirLint {
             $(
@@ -264,4 +264,4 @@ macro_rules! declare_hir_lints {
 
 pub(crate) use declare_hir_lints;
 
-use super::{Compilation, LintKind};
+use super::{Compilation, LintConfig, LintKind};