big-code-analysis 2.0.0

Tool to compute and export code metrics
Documentation
//! `Getter` implementation for C++.
#![allow(clippy::wildcard_imports, clippy::enum_glob_use)]

use super::*;

impl Getter for CppCode {
    fn get_func_space_name<'a>(node: &Node, code: &'a [u8]) -> Option<&'a str> {
        // Issue #285 contract: every `Cpp::FunctionDefinition*` alias
        // must be enumerated here AND in `get_space_kind` below AND
        // in `is_func` / `is_func_space` (see `src/checker.rs`).
        // The aliased kind_ids 489/491/494 are not emitted by the
        // currently pinned `tree-sitter-cpp` parse tables, so a
        // dropped variant would silently fall through to the
        // `_ => name-field` arm and yield the wrong name (or `None`).
        match node.kind_id().into() {
            Cpp::FunctionDefinition
            | Cpp::FunctionDefinition2
            | Cpp::FunctionDefinition3
            | Cpp::FunctionDefinition4 => {
                if let Some(op_cast) = node.first_child(|id| Cpp::OperatorCast == id) {
                    return node_text(code, &op_cast);
                }
                // we're in a function_definition so need to get the declarator
                if let Some(declarator) = node.child_by_field_name("declarator") {
                    let declarator_node = declarator;
                    if let Some(fd) = declarator_node.first_occurrence(|id| {
                        Cpp::FunctionDeclarator == id
                            || Cpp::FunctionDeclarator2 == id
                            || Cpp::FunctionDeclarator3 == id
                    }) && let Some(first) = fd.child(0)
                    {
                        match first.kind_id().into() {
                            Cpp::TypeIdentifier
                            | Cpp::Identifier
                            | Cpp::FieldIdentifier
                            | Cpp::DestructorName
                            | Cpp::OperatorName
                            | Cpp::QualifiedIdentifier
                            | Cpp::QualifiedIdentifier2
                            | Cpp::QualifiedIdentifier3
                            | Cpp::QualifiedIdentifier4
                            | Cpp::TemplateFunction
                            | Cpp::TemplateMethod => {
                                return node_text(code, &first);
                            }
                            _ => {}
                        }
                    }
                }
            }
            _ => {
                if let Some(name) = node.child_by_field_name("name") {
                    return node_text(code, &name);
                }
            }
        }
        None
    }

    fn get_space_kind(node: &Node) -> SpaceKind {
        use Cpp::*;

        // Issue #285 contract: keep every `FunctionDefinition*` alias
        // listed here — see the comment above `get_func_space_name`.
        match node.kind_id().into() {
            FunctionDefinition | FunctionDefinition2 | FunctionDefinition3
            | FunctionDefinition4 => SpaceKind::Function,
            StructSpecifier => SpaceKind::Struct,
            ClassSpecifier => SpaceKind::Class,
            NamespaceDefinition => SpaceKind::Namespace,
            TranslationUnit => SpaceKind::Unit,
            _ => SpaceKind::Unknown,
        }
    }

    fn get_op_type(node: &Node) -> HalsteadType {
        use Cpp::*;

        // `LPAREN2` here (and the `LBRACK2`/`LBRACK3` aliases in the
        // Elixir/Ruby impls) is a defensive arm, not an active one: every
        // grammar's `public_symbol_map` collapses the second-alias opener
        // to its base before `Node::kind_id()` (`ts_node_symbol`) returns,
        // so `kind_id()` never yields the alias id and the arm cannot fire
        // for real source. It guards against a future grammar bump that
        // drops that collapse — at which point the alias would also need
        // folding to its pair glyph in `get_operator_id_as_str`. The
        // invariant is pinned by `second_alias_opener_collapses_to_base_kind_id`
        // in `metrics/halstead.rs` (issue #768).
        match node.kind_id().into() {
            DOT | DOTSTAR | LPAREN | LPAREN2 | COMMA | STAR | GTGT | COLON | SEMI | Return
            | Break | Continue | If | Else | Switch | Case | Default | For | While | Goto | Do
            | Delete | New | Try | Try2 | Catch | Throw | EQ | AMPAMP | PIPEPIPE | DASH
            | DASHDASH | DASHGT | DASHGTSTAR | PLUS | PLUSPLUS | SLASH | PERCENT | PIPE | AMP
            | LTLT | TILDE | LT | LTEQ | EQEQ | BANGEQ | GTEQ | GT | GT2 | LTEQGT | PLUSEQ
            | DASHEQ | BANG | STAREQ | SLASHEQ | PERCENTEQ | GTGTEQ | LTLTEQ | AMPEQ | CARET
            | CARETEQ | PIPEEQ | LBRACK | LBRACE | QMARK | COLONCOLON | PrimitiveType
            | TypeSpecifier | Sizeof
            // A `sized_type_specifier` carries its `unsigned`/`signed`/`long`/
            // `short` modifiers as bare keyword tokens, not as `primitive_type`
            // children (`unsigned int` is `unsigned` + `primitive_type int`;
            // `signed long` and `long long` have no `primitive_type` at all).
            // Without these arms the modifiers fell into `Unknown` and were
            // dropped, so `unsigned int` collapsed to just `int` and a standalone
            // `signed long` contributed nothing to n1/N1 (issue #466). Each
            // modifier has a distinct kind_id, so keying by kind_id (the default
            // `operators` store) keeps them distinct in n1 while `long long`'s
            // two `long` tokens correctly fold to one n1 entry but two N1 hits.
            | Signed | Unsigned | Long | Short => HalsteadType::Operator,
            Identifier | TypeIdentifier | FieldIdentifier | RawStringLiteral | StringLiteral
            | NumberLiteral | True | False | Null | DOTDOTDOT => HalsteadType::Operand,
            NamespaceIdentifier => match node.parent() {
                Some(parent) if matches!(parent.kind_id().into(), NamespaceDefinition) => {
                    HalsteadType::Operand
                }
                _ => HalsteadType::Unknown,
            },
            _ => HalsteadType::Unknown,
        }
    }

    get_operator!(Cpp);
}