linter: fixes for prefer-robust-stmts (#602)

Currently only available via the LSP server, not sure it makes sense to include these as auto-fixable in the CLI. Might need a config or setting to determine what should and shouldn't be fixed.

Looked at rust-analyzer's fix API along with ruff's for inspo.

Author: sbdchd

crates/squawk/src/main.rs

@@ -217,7 +217,7 @@ Please open an issue at https://github.com/sbdchd/squawk/issues/new with the log
     let mut clap_app = Opt::clap();
     let is_stdin = !atty::is(Stream::Stdin);
     let github_annotations = std::env::var("GITHUB_ACTIONS").is_ok()
-        && !std::env::var("SQUAWK_DISABLE_GITHUB_ANNOTATIONS").is_ok();
+        && std::env::var("SQUAWK_DISABLE_GITHUB_ANNOTATIONS").is_err();
     match opts.cmd {
         Some(Command::Server) => {
             squawk_server::run().context("language server failed")?;

crates/squawk_linter/src/ignore.rs

@@ -284,7 +284,7 @@ alter table t drop column c cascade;
         let errors: Vec<_> = linter
             .lint(parse, sql)
             .into_iter()
-            .map(|x| x.code.clone())
+            .map(|x| x.code)
             .collect();
         assert!(errors.is_empty());
     }
@@ -355,7 +355,7 @@ alter table t2 drop column c2 cascade;
         let errors: Vec<_> = linter
             .lint(parse, sql)
             .into_iter()
-            .map(|x| x.code.clone())
+            .map(|x| x.code)
             .collect();
 
         assert_debug_snapshot!(errors, @r"
@@ -379,7 +379,7 @@ alter table t2 drop column c2 cascade;
         let errors: Vec<_> = linter
             .lint(parse, sql)
             .into_iter()
-            .map(|x| x.code.clone())
+            .map(|x| x.code)
             .collect();
 
         assert_debug_snapshot!(errors, @r"

crates/squawk_linter/src/lib.rs

@@ -8,6 +8,7 @@ use ignore::find_ignores;
 use ignore_index::IgnoreIndex;
 use lazy_static::lazy_static;
 use rowan::TextRange;
+use rowan::TextSize;
 use serde::{Deserialize, Serialize};
 
 use squawk_syntax::{Parse, SourceFile};
@@ -222,6 +223,36 @@ pub struct Violation {
     pub message: String,
     pub text_range: TextRange,
     pub help: Option<String>,
+    pub fix: Option<Fix>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct Fix {
+    pub title: String,
+    pub edits: Vec<Edit>,
+}
+
+impl Fix {
+    fn new<T: Into<String>>(title: T, edits: Vec<Edit>) -> Fix {
+        Fix {
+            title: title.into(),
+            edits,
+        }
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct Edit {
+    pub text_range: TextRange,
+    pub text: Option<String>,
+}
+impl Edit {
+    fn insert<T: Into<String>>(text: T, at: TextSize) -> Self {
+        Self {
+            text_range: TextRange::new(at, at),
+            text: Some(text.into()),
+        }
+    }
 }
 
 impl Violation {
@@ -237,8 +268,14 @@ impl Violation {
             text_range,
             message,
             help: help.into(),
+            fix: None,
         }
     }
+
+    fn with_fix(mut self, fix: Option<Fix>) -> Violation {
+        self.fix = fix;
+        self
+    }
 }
 
 pub struct LinterSettings {

crates/squawk_linter/src/rules/adding_field_with_default.rs

@@ -22,7 +22,7 @@ lazy_static! {
             .split('\n')
             .map(|x| x.trim())
             .filter(|x| !x.is_empty())
-            .map(|x| Identifier::new(x))
+            .map(Identifier::new)
             .collect()
     };
 }

crates/squawk_linter/src/rules/constraint_missing_not_valid.rs

@@ -5,10 +5,7 @@ use squawk_syntax::{
     ast::{self, AstNode},
 };
 
-use crate::{
-    Linter, Rule, Violation,
-    identifier::Identifier,
-};
+use crate::{Linter, Rule, Violation, identifier::Identifier};
 
 pub fn tables_created_in_transaction(
     assume_in_transaction: bool,
@@ -73,7 +70,8 @@ fn not_valid_validate_in_transaction(
                             if add_constraint.not_valid().is_some() {
                                 if let Some(constraint) = add_constraint.constraint() {
                                     if let Some(constraint_name) = constraint.name() {
-                                        not_valid_names.insert(Identifier::new(&constraint_name.text()));
+                                        not_valid_names
+                                            .insert(Identifier::new(&constraint_name.text()));
                                     }
                                 }
                             }