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 CCode {
    fn get_func_space_name<'a>(node: &Node, code: &'a [u8]) -> Option<&'a str> {
        // Issue #285 contract: every `C::FunctionDefinition*` alias must
        // be enumerated here AND in `get_space_kind` below AND in
        // `is_func` / `is_func_space` (see `src/checker.rs`). C has no
        // C++ name forms (operator-cast / destructor / operator / qualified
        // / template names), so the declarator name is a plain identifier.
        match node.kind_id().into() {
            C::FunctionDefinition | C::FunctionDefinition2 => {
                // 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| {
                        C::FunctionDeclarator == id
                            || C::FunctionDeclarator2 == id
                            || C::FunctionDeclarator3 == id
                    }) && let Some(first) = fd.child(0)
                    {
                        match first.kind_id().into() {
                            C::TypeIdentifier | C::Identifier | C::FieldIdentifier => {
                                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 C::*;

        // C has no classes/namespaces, and struct/union/enum hold no
        // functions, so the only spaces are functions and the unit
        // (matching `is_func_space` in `src/checker.rs`, #285).
        match node.kind_id().into() {
            FunctionDefinition | FunctionDefinition2 => SpaceKind::Function,
            TranslationUnit => SpaceKind::Unit,
            _ => SpaceKind::Unknown,
        }
    }

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

        // C's operator alphabet is the C++ set minus the C++-only forms
        // (`.*` / `->*`, `new` / `delete`, `try` / `catch` / `throw`,
        // `<=>`, the `>>`-closing `GT2`). Raw string literals and the
        // `namespace`-qualified identifier likewise do not exist in C.
        // `LPAREN2` is a defensive arm (collapsed to `LPAREN` before
        // `kind_id()`; #768, see the Cpp note).
        match node.kind_id().into() {
            DOT | LPAREN | LPAREN2 | COMMA | STAR | GTGT | COLON | SEMI | Return | Break
            | Continue | If | Else | Switch | Case | Default | For | While | Goto | Do | EQ
            | AMPAMP | PIPEPIPE | DASH | DASHDASH | DASHGT | PLUS | PLUSPLUS | SLASH | PERCENT
            | PIPE | AMP | LTLT | TILDE | LT | LTEQ | EQEQ | BANGEQ | GTEQ | GT | PLUSEQ
            | DASHEQ | BANG | STAREQ | SLASHEQ | PERCENTEQ | GTGTEQ | LTLTEQ | AMPEQ | CARET
            | CARETEQ | PIPEEQ | LBRACK | LBRACE | QMARK | 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 fall into `Unknown` and are
            // dropped, so `unsigned int` collapses to just `int` and a standalone
            // `signed long` contributes 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 | StringLiteral | NumberLiteral
            | True | False | Null | DOTDOTDOT => HalsteadType::Operand,
            _ => HalsteadType::Unknown,
        }
    }

    get_operator!(C);
}