SSR: Support statement matching and replacing

crates/parser/src/grammar.rs

@@ -66,6 +66,10 @@ pub(crate) mod fragments {
         expressions::stmt(p, expressions::StmtWithSemi::No)
     }
 
+    pub(crate) fn stmt_optional_semi(p: &mut Parser) {
+        expressions::stmt(p, expressions::StmtWithSemi::Optional)
+    }
+
     pub(crate) fn opt_visibility(p: &mut Parser) {
         let _ = super::opt_visibility(p);
     }

crates/parser/src/lib.rs

@@ -88,6 +88,7 @@ pub enum FragmentKind {
     Path,
     Expr,
     Statement,
+    StatementOptionalSemi,
     Type,
     Pattern,
     Item,
@@ -118,6 +119,7 @@ pub fn parse_fragment(
         FragmentKind::Visibility => grammar::fragments::opt_visibility,
         FragmentKind::MetaItem => grammar::fragments::meta_item,
         FragmentKind::Statement => grammar::fragments::stmt,
+        FragmentKind::StatementOptionalSemi => grammar::fragments::stmt_optional_semi,
         FragmentKind::Items => grammar::fragments::macro_items,
         FragmentKind::Statements => grammar::fragments::macro_stmts,
         FragmentKind::Attr => grammar::fragments::attr,

crates/ssr/src/parsing.rs

@@ -78,6 +78,7 @@ impl ParsedRule {
         builder.try_add(ast::Item::parse(&raw_pattern), raw_template.map(ast::Item::parse));
         builder.try_add(ast::Path::parse(&raw_pattern), raw_template.map(ast::Path::parse));
         builder.try_add(ast::Pat::parse(&raw_pattern), raw_template.map(ast::Pat::parse));
+        builder.try_add(ast::Stmt::parse(&raw_pattern), raw_template.map(ast::Stmt::parse));
         builder.build()
     }
 }

crates/ssr/src/tests.rs

@@ -159,6 +159,50 @@ fn assert_match_failure_reason(pattern: &str, code: &str, snippet: &str, expecte
     assert_eq!(reasons, vec![expected_reason]);
 }
 
+#[test]
+fn ssr_let_stmt_in_macro_match() {
+    assert_matches(
+        "let a = 0",
+        r#"
+            macro_rules! m1 { ($a:stmt) => {$a}; }
+            fn f() {m1!{ let a = 0 };}"#,
+        // FIXME: Whitespace is not part of the matched block
+        &["leta=0"],
+    );
+}
+
+#[test]
+fn ssr_let_stmt_in_fn_match() {
+    assert_matches("let $a = 10;", "fn main() { let x = 10; x }", &["let x = 10;"]);
+    assert_matches("let $a = $b;", "fn main() { let x = 10; x }", &["let x = 10;"]);
+}
+
+#[test]
+fn ssr_block_expr_match() {
+    assert_matches("{ let $a = $b; }", "fn main() { let x = 10; }", &["{ let x = 10; }"]);
+    assert_matches("{ let $a = $b; $c }", "fn main() { let x = 10; x }", &["{ let x = 10; x }"]);
+}
+
+#[test]
+fn ssr_let_stmt_replace() {
+    // Pattern and template with trailing semicolon
+    assert_ssr_transform(
+        "let $a = $b; ==>> let $a = 11;",
+        "fn main() { let x = 10; x }",
+        expect![["fn main() { let x = 11; x }"]],
+    );
+}
+
+#[test]
+fn ssr_let_stmt_replace_expr() {
+    // Trailing semicolon should be dropped from the new expression
+    assert_ssr_transform(
+        "let $a = $b; ==>> $b",
+        "fn main() { let x = 10; }",
+        expect![["fn main() { 10 }"]],
+    );
+}
+
 #[test]
 fn ssr_function_to_method() {
     assert_ssr_transform(

crates/syntax/src/lib.rs

@@ -212,6 +212,13 @@ impl ast::Attr {
     }
 }
 
+impl ast::Stmt {
+    /// Returns `text`, parsed as statement, but only if it has no errors.
+    pub fn parse(text: &str) -> Result<Self, ()> {
+        parsing::parse_text_fragment(text, parser::FragmentKind::StatementOptionalSemi)
+    }
+}
+
 /// Matches a `SyntaxNode` against an `ast` type.
 ///
 /// # Example:

crates/syntax/src/tests.rs

@@ -102,6 +102,15 @@ fn type_parser_tests() {
     );
 }
 
+#[test]
+fn stmt_parser_tests() {
+    fragment_parser_dir_test(
+        &["parser/fragments/stmt/ok"],
+        &["parser/fragments/stmt/err"],
+        crate::ast::Stmt::parse,
+    );
+}
+
 #[test]
 fn parser_fuzz_tests() {
     for (_, text) in collect_rust_files(&test_data_dir(), &["parser/fuzz-failures"]) {

crates/syntax/test_data/parser/fragments/stmt/err/0000_attr.rast

@@ -0,0 +1 @@
+ERROR

crates/syntax/test_data/parser/fragments/stmt/err/0000_attr.rs

@@ -0,0 +1 @@
+#[foo]

crates/syntax/test_data/parser/fragments/stmt/err/0000_multiple_stmts.rast

@@ -0,0 +1 @@
+ERROR

crates/syntax/test_data/parser/fragments/stmt/err/0000_multiple_stmts.rs

@@ -0,0 +1 @@
+a(); b(); c()

crates/syntax/test_data/parser/fragments/stmt/err/0000_open_parenthesis.rast

@@ -0,0 +1 @@
+ERROR

crates/syntax/test_data/parser/fragments/stmt/err/0000_open_parenthesis.rs

@@ -0,0 +1 @@
+(

crates/syntax/test_data/parser/fragments/stmt/err/0000_semicolon.rast

@@ -0,0 +1 @@
+ERROR

crates/syntax/test_data/parser/fragments/stmt/err/0000_semicolon.rs

@@ -0,0 +1 @@
+;

crates/syntax/test_data/parser/fragments/stmt/err/0000_unterminated_expr.rast

@@ -0,0 +1 @@
+ERROR

crates/syntax/test_data/parser/fragments/stmt/err/0000_unterminated_expr.rs

@@ -0,0 +1 @@
+1 +

crates/syntax/test_data/parser/fragments/stmt/ok/0000_expr.rast

@@ -0,0 +1,9 @@
+[email protected]
+  [email protected]
+    [email protected]
+      [email protected] "1"
+    [email protected] " "
+    [email protected] "+"
+    [email protected] " "
+    [email protected]
+      [email protected] "1"

crates/syntax/test_data/parser/fragments/stmt/ok/0000_expr.rs

@@ -0,0 +1 @@
+1 + 1

crates/syntax/test_data/parser/fragments/stmt/ok/0000_expr_block.rast

@@ -0,0 +1,69 @@
+[email protected]
+  [email protected]
+    [email protected] "{"
+    [email protected] "\n    "
+    [email protected]
+      [email protected] "let"
+      [email protected] " "
+      [email protected]
+        [email protected]
+          [email protected] "x"
+      [email protected] " "
+      [email protected] "="
+      [email protected] " "
+      [email protected]
+        [email protected]
+          [email protected]
+            [email protected]
+              [email protected]
+                [email protected] "foo"
+        [email protected]
+          [email protected] "("
+          [email protected] ")"
+      [email protected] ";"
+    [email protected] "\n    "
+    [email protected]
+      [email protected] "let"
+      [email protected] " "
+      [email protected]
+        [email protected]
+          [email protected] "y"
+      [email protected] " "
+      [email protected] "="
+      [email protected] " "
+      [email protected]
+        [email protected]
+          [email protected]
+            [email protected]
+              [email protected]
+                [email protected] "bar"
+        [email protected]
+          [email protected] "("
+          [email protected] ")"
+      [email protected] ";"
+    [email protected] "\n    "
+    [email protected]
+      [email protected]
+        [email protected]
+          [email protected]
+            [email protected]
+              [email protected] "Ok"
+      [email protected]
+        [email protected] "("
+        [email protected]
+          [email protected]
+            [email protected]
+              [email protected]
+                [email protected]
+                  [email protected] "x"
+          [email protected] " "
+          [email protected] "+"
+          [email protected] " "
+          [email protected]
+            [email protected]
+              [email protected]
+                [email protected]
+                  [email protected] "y"
+        [email protected] ")"
+    [email protected] "\n"
+    [email protected] "}"

crates/syntax/test_data/parser/fragments/stmt/ok/0000_expr_block.rs

@@ -0,0 +1,5 @@
+{
+    let x = foo();
+    let y = bar();
+    Ok(x + y)
+}

crates/syntax/test_data/parser/fragments/stmt/ok/0000_fn_call.rast

@@ -0,0 +1,11 @@
+[email protected]
+  [email protected]
+    [email protected]
+      [email protected]
+        [email protected]
+          [email protected]
+            [email protected] "foo"
+    [email protected]
+      [email protected] "("
+      [email protected] ")"
+  [email protected] ";"

crates/syntax/test_data/parser/fragments/stmt/ok/0000_fn_call.rs

@@ -0,0 +1 @@
+foo();

crates/syntax/test_data/parser/fragments/stmt/ok/0000_let_stmt.rast

@@ -0,0 +1,12 @@
+[email protected]
+  [email protected] "let"
+  [email protected] " "
+  [email protected]
+    [email protected]
+      [email protected] "x"
+  [email protected] " "
+  [email protected] "="
+  [email protected] " "
+  [email protected]
+    [email protected] "10"
+  [email protected] ";"

crates/syntax/test_data/parser/fragments/stmt/ok/0000_let_stmt.rs

@@ -0,0 +1 @@
+let x = 10;

crates/syntax/test_data/parser/fragments/stmt/ok/0000_macro_let_stmt.rast

@@ -0,0 +1,21 @@
+[email protected]
+  [email protected]
+    [email protected]
+      [email protected]
+        [email protected]
+          [email protected] "m1"
+    [email protected] "!"
+    [email protected]
+      [email protected] "{"
+      [email protected] " "
+      [email protected] "let"
+      [email protected] " "
+      [email protected] "a"
+      [email protected] " "
+      [email protected] "="
+      [email protected] " "
+      [email protected] "0"
+      [email protected] ";"
+      [email protected] " "
+      [email protected] "}"
+  [email protected] ";"

crates/syntax/test_data/parser/fragments/stmt/ok/0000_macro_let_stmt.rs

@@ -0,0 +1 @@
+m1!{ let a = 0; };

crates/syntax/test_data/parser/fragments/stmt/ok/0000_macro_unterminated_let_stmt.rast

@@ -0,0 +1,21 @@
+[email protected]
+  [email protected]
+    [email protected]
+      [email protected]
+        [email protected]
+          [email protected] "m1"
+    [email protected] "!"
+    [email protected]
+      [email protected] "{"
+      [email protected] " "
+      [email protected] "let"
+      [email protected] " "
+      [email protected] "a"
+      [email protected] " "
+      [email protected] "="
+      [email protected] " "
+      [email protected] "0"
+      [email protected] ";"
+      [email protected] " "
+      [email protected] "}"
+  [email protected] ";"

crates/syntax/test_data/parser/fragments/stmt/ok/0000_macro_unterminated_let_stmt.rs

@@ -0,0 +1 @@
+m1!{ let a = 0; };

crates/syntax/test_data/parser/fragments/stmt/ok/0000_struct_item.rast

@@ -0,0 +1,22 @@
+[email protected]
+  [email protected] "struct"
+  [email protected] " "
+  [email protected]
+    [email protected] "Foo"
+  [email protected] " "
+  [email protected]
+    [email protected] "{"
+    [email protected] "\n    "
+    [email protected]
+      [email protected]
+        [email protected] "bar"
+      [email protected] ":"
+      [email protected] " "
+      [email protected]
+        [email protected]
+          [email protected]
+            [email protected]
+              [email protected] "u32"
+    [email protected] ","
+    [email protected] "\n"
+    [email protected] "}"

crates/syntax/test_data/parser/fragments/stmt/ok/0000_struct_item.rs

@@ -0,0 +1,3 @@
+struct Foo {
+    bar: u32,
+}

crates/syntax/test_data/parser/fragments/stmt/ok/0000_unterminated_fn_call.rast

@@ -0,0 +1,10 @@
+[email protected]
+  [email protected]
+    [email protected]
+      [email protected]
+        [email protected]
+          [email protected]
+            [email protected] "foo"
+    [email protected]
+      [email protected] "("
+      [email protected] ")"

crates/syntax/test_data/parser/fragments/stmt/ok/0000_unterminated_fn_call.rs

@@ -0,0 +1 @@
+foo()

crates/syntax/test_data/parser/fragments/stmt/ok/0000_unterminated_let_stmt.rast

@@ -0,0 +1,11 @@
+[email protected]
+  [email protected] "let"
+  [email protected] " "
+  [email protected]
+    [email protected]
+      [email protected] "x"
+  [email protected] " "
+  [email protected] "="
+  [email protected] " "
+  [email protected]
+    [email protected] "10"

crates/syntax/test_data/parser/fragments/stmt/ok/0000_unterminated_let_stmt.rs

@@ -0,0 +1 @@
+let x = 10