| 1 | use react_compiler_ast::File; |
| 2 | use react_compiler_ast::declarations::{Declaration, ExportDefaultDecl}; |
| 3 | use react_compiler_ast::expressions::Expression; |
| 4 | use react_compiler_ast::statements::Statement; |
| 5 | use react_compiler_lowering::FunctionNode; |
| 6 | |
| 7 | /// Count the number of top-level functions in an AST file. |
| 8 | /// |
| 9 | /// "Top-level" means: |
| 10 | /// - FunctionDeclaration at program body level |
| 11 | /// - FunctionExpression/ArrowFunctionExpression in a VariableDeclarator at program body level |
| 12 | /// - FunctionDeclaration inside ExportNamedDeclaration |
| 13 | /// - FunctionDeclaration/FunctionExpression/ArrowFunctionExpression inside ExportDefaultDeclaration |
| 14 | /// - VariableDeclaration with function expressions inside ExportNamedDeclaration |
| 15 | /// |
| 16 | /// This matches the TS test binary's traversal behavior. |
| 17 | pub fn count_top_level_functions(ast: &File) -> usize { |
| 18 | let mut count = 0; |
| 19 | for stmt in &ast.program.body { |
| 20 | count += count_functions_in_statement(stmt); |
| 21 | } |
| 22 | count |
| 23 | } |
| 24 | |
| 25 | fn count_functions_in_statement(stmt: &Statement) -> usize { |
| 26 | match stmt { |
| 27 | Statement::FunctionDeclaration(_) => 1, |
| 28 | Statement::VariableDeclaration(var_decl) => { |
| 29 | let mut count = 0; |
| 30 | for declarator in &var_decl.declarations { |
| 31 | if let Some(init) = &declarator.init { |
| 32 | if is_function_expression(init) { |
| 33 | count += 1; |
| 34 | } |
| 35 | } |
| 36 | } |
| 37 | count |
| 38 | } |
| 39 | Statement::ExportNamedDeclaration(export) => { |
| 40 | if let Some(decl) = &export.declaration { |
| 41 | match decl.as_ref() { |
| 42 | Declaration::FunctionDeclaration(_) => 1, |
| 43 | Declaration::VariableDeclaration(var_decl) => { |
| 44 | let mut count = 0; |
| 45 | for declarator in &var_decl.declarations { |
| 46 | if let Some(init) = &declarator.init { |
| 47 | if is_function_expression(init) { |
| 48 | count += 1; |
| 49 | } |
| 50 | } |
| 51 | } |
| 52 | count |
| 53 | } |
| 54 | _ => 0, |
| 55 | } |
| 56 | } else { |
| 57 | 0 |
| 58 | } |
| 59 | } |
| 60 | Statement::ExportDefaultDeclaration(export) => match export.declaration.as_ref() { |
| 61 | ExportDefaultDecl::FunctionDeclaration(_) => 1, |
| 62 | ExportDefaultDecl::Expression(expr) => { |
| 63 | if is_function_expression(expr) { |
| 64 | 1 |
| 65 | } else { |
| 66 | 0 |
| 67 | } |
| 68 | } |
| 69 | _ => 0, |
| 70 | }, |
| 71 | // Expression statements with function expressions (uncommon but possible) |
| 72 | Statement::ExpressionStatement(expr_stmt) => { |
| 73 | if is_function_expression(&expr_stmt.expression) { |
| 74 | 1 |
| 75 | } else { |
| 76 | 0 |
| 77 | } |
| 78 | } |
| 79 | _ => 0, |
| 80 | } |
| 81 | } |
| 82 | |
| 83 | fn is_function_expression(expr: &Expression) -> bool { |
| 84 | matches!( |
| 85 | expr, |
| 86 | Expression::FunctionExpression(_) | Expression::ArrowFunctionExpression(_) |
| 87 | ) |
| 88 | } |
| 89 | |
| 90 | /// Extract the nth top-level function from an AST file as a `FunctionNode`. |
| 91 | /// Also returns the inferred name (e.g. from a variable declarator). |
| 92 | /// Returns None if function_index is out of bounds. |
| 93 | pub fn extract_function( |
| 94 | ast: &File, |
| 95 | function_index: usize, |
| 96 | ) -> Option<(FunctionNode<'_>, Option<&str>)> { |
| 97 | let mut index = 0usize; |
| 98 | |
| 99 | for stmt in &ast.program.body { |
| 100 | match stmt { |
| 101 | Statement::FunctionDeclaration(func_decl) => { |
| 102 | if index == function_index { |
| 103 | let name = func_decl.id.as_ref().map(|id| id.name.as_str()); |
| 104 | return Some((FunctionNode::FunctionDeclaration(func_decl), name)); |
| 105 | } |
| 106 | index += 1; |
| 107 | } |
| 108 | Statement::VariableDeclaration(var_decl) => { |
| 109 | for declarator in &var_decl.declarations { |
| 110 | if let Some(init) = &declarator.init { |
| 111 | match init.as_ref() { |
| 112 | Expression::FunctionExpression(func) => { |
| 113 | if index == function_index { |
| 114 | let name = match &declarator.id { |
| 115 | react_compiler_ast::patterns::PatternLike::Identifier( |
| 116 | ident, |
| 117 | ) => Some(ident.name.as_str()), |
| 118 | _ => func.id.as_ref().map(|id| id.name.as_str()), |
| 119 | }; |
| 120 | return Some((FunctionNode::FunctionExpression(func), name)); |
| 121 | } |
| 122 | index += 1; |
| 123 | } |
| 124 | Expression::ArrowFunctionExpression(arrow) => { |
| 125 | if index == function_index { |
| 126 | let name = match &declarator.id { |
| 127 | react_compiler_ast::patterns::PatternLike::Identifier( |
| 128 | ident, |
| 129 | ) => Some(ident.name.as_str()), |
| 130 | _ => None, |
| 131 | }; |
| 132 | return Some(( |
| 133 | FunctionNode::ArrowFunctionExpression(arrow), |
| 134 | name, |
| 135 | )); |
| 136 | } |
| 137 | index += 1; |
| 138 | } |
| 139 | _ => {} |
| 140 | } |
| 141 | } |
| 142 | } |
| 143 | } |
| 144 | Statement::ExportNamedDeclaration(export) => { |
| 145 | if let Some(decl) = &export.declaration { |
| 146 | match decl.as_ref() { |
| 147 | Declaration::FunctionDeclaration(func_decl) => { |
| 148 | if index == function_index { |
| 149 | let name = func_decl.id.as_ref().map(|id| id.name.as_str()); |
| 150 | return Some((FunctionNode::FunctionDeclaration(func_decl), name)); |
| 151 | } |
| 152 | index += 1; |
| 153 | } |
| 154 | Declaration::VariableDeclaration(var_decl) => { |
| 155 | for declarator in &var_decl.declarations { |
| 156 | if let Some(init) = &declarator.init { |
| 157 | match init.as_ref() { |
| 158 | Expression::FunctionExpression(func) => { |
| 159 | if index == function_index { |
| 160 | let name = match &declarator.id { |
| 161 | react_compiler_ast::patterns::PatternLike::Identifier(ident) => Some(ident.name.as_str()), |
| 162 | _ => func.id.as_ref().map(|id| id.name.as_str()), |
| 163 | }; |
| 164 | return Some(( |
| 165 | FunctionNode::FunctionExpression(func), |
| 166 | name, |
| 167 | )); |
| 168 | } |
| 169 | index += 1; |
| 170 | } |
| 171 | Expression::ArrowFunctionExpression(arrow) => { |
| 172 | if index == function_index { |
| 173 | let name = match &declarator.id { |
| 174 | react_compiler_ast::patterns::PatternLike::Identifier(ident) => Some(ident.name.as_str()), |
| 175 | _ => None, |
| 176 | }; |
| 177 | return Some(( |
| 178 | FunctionNode::ArrowFunctionExpression(arrow), |
| 179 | name, |
| 180 | )); |
| 181 | } |
| 182 | index += 1; |
| 183 | } |
| 184 | _ => {} |
| 185 | } |
| 186 | } |
| 187 | } |
| 188 | } |
| 189 | _ => {} |
| 190 | } |
| 191 | } |
| 192 | } |
| 193 | Statement::ExportDefaultDeclaration(export) => match export.declaration.as_ref() { |
| 194 | ExportDefaultDecl::FunctionDeclaration(func_decl) => { |
| 195 | if index == function_index { |
| 196 | let name = func_decl.id.as_ref().map(|id| id.name.as_str()); |
| 197 | return Some((FunctionNode::FunctionDeclaration(func_decl), name)); |
| 198 | } |
| 199 | index += 1; |
| 200 | } |
| 201 | ExportDefaultDecl::Expression(expr) => match expr.as_ref() { |
| 202 | Expression::FunctionExpression(func) => { |
| 203 | if index == function_index { |
| 204 | let name = func.id.as_ref().map(|id| id.name.as_str()); |
| 205 | return Some((FunctionNode::FunctionExpression(func), name)); |
| 206 | } |
| 207 | index += 1; |
| 208 | } |
| 209 | Expression::ArrowFunctionExpression(arrow) => { |
| 210 | if index == function_index { |
| 211 | return Some((FunctionNode::ArrowFunctionExpression(arrow), None)); |
| 212 | } |
| 213 | index += 1; |
| 214 | } |
| 215 | _ => {} |
| 216 | }, |
| 217 | _ => {} |
| 218 | }, |
| 219 | Statement::ExpressionStatement(expr_stmt) => match expr_stmt.expression.as_ref() { |
| 220 | Expression::FunctionExpression(func) => { |
| 221 | if index == function_index { |
| 222 | let name = func.id.as_ref().map(|id| id.name.as_str()); |
| 223 | return Some((FunctionNode::FunctionExpression(func), name)); |
| 224 | } |
| 225 | index += 1; |
| 226 | } |
| 227 | Expression::ArrowFunctionExpression(arrow) => { |
| 228 | if index == function_index { |
| 229 | return Some((FunctionNode::ArrowFunctionExpression(arrow), None)); |
| 230 | } |
| 231 | index += 1; |
| 232 | } |
| 233 | _ => {} |
| 234 | }, |
| 235 | _ => {} |
| 236 | } |
| 237 | } |
| 238 | None |
| 239 | } |