rule: add back transaction nesting to v2

.vscode/linter.code-snippets

@@ -0,0 +1,37 @@
+{
+	// Place your tea workspace snippets here. Each snippet is defined under a snippet name and has a scope, prefix, body and 
+	// description. Add comma separated ids of the languages where the snippet is applicable in the scope field. If scope 
+	// is left empty or omitted, the snippet gets applied to all languages. The prefix is what is 
+	// used to trigger the snippet and the body will be expanded and inserted. Possible variables are: 
+	// $1, $2 for tab stops, $0 for the final cursor position, and ${1:label}, ${2:another} for placeholders. 
+	// Placeholders with the same ids are connected.
+	// Example:
+	// "Print to console": {
+	// 	"scope": "javascript,typescript",
+	// 	"prefix": "log",
+	// 	"body": [
+	// 		"console.log('$1');",
+	// 		"$2"
+	// 	],
+	// 	"description": "Log output to console"
+	// }
+
+    "linttest": {
+        "scope": "rust",
+        "prefix": "linttest",
+        "body": [
+"#[test]",
+"fn $1() {",
+"    let sql = r#\"",
+"$2",
+"    \"#;",
+"",
+"    let file = SourceFile::parse(&sql);",
+"    let mut linter = Linter::new([Rule::$3]);",
+"    let errors = linter.lint(file, sql);",
+"    assert_debug_snapshot!(errors);",
+"}",
+
+        ]
+    }
+}

.vscode/syntax.code-snippets

@@ -0,0 +1,83 @@
+{
+	// Place your tea workspace snippets here. Each snippet is defined under a snippet name and has a scope, prefix, body and 
+	// description. Add comma separated ids of the languages where the snippet is applicable in the scope field. If scope 
+	// is left empty or omitted, the snippet gets applied to all languages. The prefix is what is 
+	// used to trigger the snippet and the body will be expanded and inserted. Possible variables are: 
+	// $1, $2 for tab stops, $0 for the final cursor position, and ${1:label}, ${2:another} for placeholders. 
+	// Placeholders with the same ids are connected.
+	// Example:
+	// "Print to console": {
+	// 	"scope": "javascript,typescript",
+	// 	"prefix": "log",
+	// 	"body": [
+	// 		"console.log('$1');",
+	// 		"$2"
+	// 	],
+	// 	"description": "Log output to console"
+	// }
+    "astnode": {
+        "scope": "rust",
+        "prefix": "astnode",
+        "body": [
+
+"#[derive(Debug, Clone, PartialEq, Eq, Hash)]",
+"pub struct $1 {",
+"    pub(crate) syntax: SyntaxNode,",
+"}",
+"",
+"impl AstNode for $1 {",
+"    #[inline]",
+"    fn can_cast(kind: SyntaxKind) -> bool {",
+"        kind == SyntaxKind::$2",
+"    }",
+"    #[inline]",
+"    fn cast(syntax: SyntaxNode) -> Option<Self> {",
+"        if Self::can_cast(syntax.kind()) {",
+"            Some(Self { syntax })",
+"        } else {",
+"            None",
+"        }",
+"    }",
+"    #[inline]",
+"    fn syntax(&self) -> &SyntaxNode {",
+"        &self.syntax",
+"    }",
+"}",
+
+        ]
+    },
+    "astenum": {
+        "scope": "rust",
+        "prefix": "astenum",
+        "body": [
+"#[derive(Debug, Clone, PartialEq, Eq, Hash)]",
+"pub enum $1 {",
+"    $3($3),",
+"}",
+"",
+"impl AstNode for $1 {",
+"    #[inline]",
+"    fn can_cast(kind: SyntaxKind) -> bool {",
+"        matches!(kind, SyntaxKind::$2)",
+"    }",
+"    #[inline]",
+"    fn cast(syntax: SyntaxNode) -> Option<Self> {",
+"        let res = match syntax.kind() {",
+"            SyntaxKind::DEFAULT_CONSTRAINT => {",
+"                $1::$3($3 { syntax })",
+"            }",
+"            _ => return None,",
+"        };",
+"        Some(res)",
+"    }",
+"    #[inline]",
+"    fn syntax(&self) -> &SyntaxNode {",
+"        match self {",
+"            $1::$3(it) => &it.syntax,",
+"        }",
+"    }",
+"}",
+
+        ]
+    }
+}

crates/squawk_linter/src/lib.rs

@@ -47,6 +47,7 @@ use rules::renaming_column;
 use rules::renaming_table;
 use rules::require_concurrent_index_creation;
 use rules::require_concurrent_index_deletion;
+use rules::transaction_nesting;
 // xtask:new-lint:rule-import
 
 #[derive(Debug, PartialEq, Clone, Copy, Serialize, Hash, Eq, Deserialize, Sequence)]
@@ -340,6 +341,9 @@ impl Linter {
         if self.rules.contains(&Rule::BanAlterDomainWithAddConstraint) {
             ban_alter_domain_with_add_constraint(self, &file);
         }
+        if self.rules.contains(&Rule::TransactionNesting) {
+            transaction_nesting(self, &file);
+        }
         // xtask:new-lint:rule-call
 
         // locate any ignores in the file

crates/squawk_linter/src/rules/mod.rs

@@ -24,6 +24,7 @@ pub(crate) mod renaming_column;
 pub(crate) mod renaming_table;
 pub(crate) mod require_concurrent_index_creation;
 pub(crate) mod require_concurrent_index_deletion;
+pub(crate) mod transaction_nesting;
 // xtask:new-lint:mod-decl
 
 pub(crate) use adding_field_with_default::adding_field_with_default;
@@ -52,4 +53,5 @@ pub(crate) use renaming_column::renaming_column;
 pub(crate) use renaming_table::renaming_table;
 pub(crate) use require_concurrent_index_creation::require_concurrent_index_creation;
 pub(crate) use require_concurrent_index_deletion::require_concurrent_index_deletion;
+pub(crate) use transaction_nesting::transaction_nesting;
 // xtask:new-lint:export

crates/squawk_linter/src/rules/snapshots/squawk_linter__rules__transaction_nesting__test__begin_assume_transaction_err.snap

@@ -0,0 +1,30 @@
+---
+source: crates/squawk_linter/src/rules/transaction_nesting.rs
+expression: errors
+---
+[
+    Violation {
+        code: TransactionNesting,
+        message: "There is an existing transaction already in progress, managed by your migration tool.",
+        text_range: 1..6,
+        help: Some(
+            "Put migration statements in separate files to have them be in separate transactions or don't use the assume-in-transaction setting.",
+        ),
+    },
+    Violation {
+        code: TransactionNesting,
+        message: "There is an existing transaction already in progress, managed by your migration tool.",
+        text_range: 8..13,
+        help: Some(
+            "Put migration statements in separate files to have them be in separate transactions or don't use the assume-in-transaction setting.",
+        ),
+    },
+    Violation {
+        code: TransactionNesting,
+        message: "Attempting to end the transaction that is managed by your migration tool",
+        text_range: 25..31,
+        help: Some(
+            "Put migration statements in separate files to have them be in separate transactions or don't use the assume-in-transaction setting.",
+        ),
+    },
+]

crates/squawk_linter/src/rules/snapshots/squawk_linter__rules__transaction_nesting__test__begin_repeated_err.snap

@@ -0,0 +1,14 @@
+---
+source: crates/squawk_linter/src/rules/transaction_nesting.rs
+expression: errors
+---
+[
+    Violation {
+        code: TransactionNesting,
+        message: "There is an existing transaction already in progress.",
+        text_range: 8..13,
+        help: Some(
+            "Put migration statements in separate files to have them be in separate transactions or don't use the assume-in-transaction setting.",
+        ),
+    },
+]

crates/squawk_linter/src/rules/snapshots/squawk_linter__rules__transaction_nesting__test__commit_repeated_err.snap

@@ -0,0 +1,14 @@
+---
+source: crates/squawk_linter/src/rules/transaction_nesting.rs
+expression: errors
+---
+[
+    Violation {
+        code: TransactionNesting,
+        message: "There is no transaction to `COMMIT` or `ROLLBACK`.",
+        text_range: 26..32,
+        help: Some(
+            "`BEGIN` a transaction at an earlier point in the migration or remove this statement.",
+        ),
+    },
+]

crates/squawk_linter/src/rules/snapshots/squawk_linter__rules__transaction_nesting__test__commit_with_assume_in_transaction_err.snap

@@ -0,0 +1,14 @@
+---
+source: crates/squawk_linter/src/rules/transaction_nesting.rs
+expression: errors
+---
+[
+    Violation {
+        code: TransactionNesting,
+        message: "Attempting to end the transaction that is managed by your migration tool",
+        text_range: 11..17,
+        help: Some(
+            "Put migration statements in separate files to have them be in separate transactions or don't use the assume-in-transaction setting.",
+        ),
+    },
+]

crates/squawk_linter/src/rules/snapshots/squawk_linter__rules__transaction_nesting__test__rollback_with_assume_in_transaction_err.snap

@@ -0,0 +1,14 @@
+---
+source: crates/squawk_linter/src/rules/transaction_nesting.rs
+expression: errors
+---
+[
+    Violation {
+        code: TransactionNesting,
+        message: "Attempting to end the transaction that is managed by your migration tool",
+        text_range: 92..100,
+        help: Some(
+            "Put migration statements in separate files to have them be in separate transactions or don't use the assume-in-transaction setting.",
+        ),
+    },
+]