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|
use ide_db::base_db::{FileId, SourceDatabase};
use ide_db::RootDatabase;
use syntax::{
algo, AstNode, NodeOrToken, SourceFile, SyntaxKind::STRING, SyntaxToken, TextRange, TextSize,
};
// Feature: Show Syntax Tree
//
// Shows the parse tree of the current file. It exists mostly for debugging
// rust-analyzer itself.
//
// |===
// | Editor | Action Name
//
// | VS Code | **Rust Analyzer: Show Syntax Tree**
// |===
pub(crate) fn syntax_tree(
db: &RootDatabase,
file_id: FileId,
text_range: Option<TextRange>,
) -> String {
let parse = db.parse(file_id);
if let Some(text_range) = text_range {
let node = match algo::find_covering_element(parse.tree().syntax(), text_range) {
NodeOrToken::Node(node) => node,
NodeOrToken::Token(token) => {
if let Some(tree) = syntax_tree_for_string(&token, text_range) {
return tree;
}
token.parent()
}
};
format!("{:#?}", node)
} else {
format!("{:#?}", parse.tree().syntax())
}
}
/// Attempts parsing the selected contents of a string literal
/// as rust syntax and returns its syntax tree
fn syntax_tree_for_string(token: &SyntaxToken, text_range: TextRange) -> Option<String> {
// When the range is inside a string
// we'll attempt parsing it as rust syntax
// to provide the syntax tree of the contents of the string
match token.kind() {
STRING => syntax_tree_for_token(token, text_range),
_ => None,
}
}
fn syntax_tree_for_token(node: &SyntaxToken, text_range: TextRange) -> Option<String> {
// Range of the full node
let node_range = node.text_range();
let text = node.text().to_string();
// We start at some point inside the node
// Either we have selected the whole string
// or our selection is inside it
let start = text_range.start() - node_range.start();
// how many characters we have selected
let len = text_range.len();
let node_len = node_range.len();
let start = start;
// We want to cap our length
let len = len.min(node_len);
// Ensure our slice is inside the actual string
let end =
if start + len < TextSize::of(&text) { start + len } else { TextSize::of(&text) - start };
let text = &text[TextRange::new(start, end)];
// Remove possible extra string quotes from the start
// and the end of the string
let text = text
.trim_start_matches('r')
.trim_start_matches('#')
.trim_start_matches('"')
.trim_end_matches('#')
.trim_end_matches('"')
.trim()
// Remove custom markers
.replace("<|>", "");
let parsed = SourceFile::parse(&text);
// If the "file" parsed without errors,
// return its syntax
if parsed.errors().is_empty() {
return Some(format!("{:#?}", parsed.tree().syntax()));
}
None
}
#[cfg(test)]
mod tests {
use test_utils::assert_eq_text;
use crate::fixture;
#[test]
fn test_syntax_tree_without_range() {
// Basic syntax
let (analysis, file_id) = fixture::file(r#"fn foo() {}"#);
let syn = analysis.syntax_tree(file_id, None).unwrap();
assert_eq_text!(
syn.trim(),
r#"
SOURCE_FILE@0..11
FN@0..11
FN_KW@0..2 "fn"
WHITESPACE@2..3 " "
NAME@3..6
IDENT@3..6 "foo"
PARAM_LIST@6..8
L_PAREN@6..7 "("
R_PAREN@7..8 ")"
WHITESPACE@8..9 " "
BLOCK_EXPR@9..11
L_CURLY@9..10 "{"
R_CURLY@10..11 "}"
"#
.trim()
);
let (analysis, file_id) = fixture::file(
r#"
fn test() {
assert!("
fn foo() {
}
", "");
}"#
.trim(),
);
let syn = analysis.syntax_tree(file_id, None).unwrap();
assert_eq_text!(
syn.trim(),
r#"
SOURCE_FILE@0..60
FN@0..60
FN_KW@0..2 "fn"
WHITESPACE@2..3 " "
NAME@3..7
IDENT@3..7 "test"
PARAM_LIST@7..9
L_PAREN@7..8 "("
R_PAREN@8..9 ")"
WHITESPACE@9..10 " "
BLOCK_EXPR@10..60
L_CURLY@10..11 "{"
WHITESPACE@11..16 "\n "
EXPR_STMT@16..58
MACRO_CALL@16..57
PATH@16..22
PATH_SEGMENT@16..22
NAME_REF@16..22
IDENT@16..22 "assert"
BANG@22..23 "!"
TOKEN_TREE@23..57
L_PAREN@23..24 "("
STRING@24..52 "\"\n fn foo() {\n ..."
COMMA@52..53 ","
WHITESPACE@53..54 " "
STRING@54..56 "\"\""
R_PAREN@56..57 ")"
SEMICOLON@57..58 ";"
WHITESPACE@58..59 "\n"
R_CURLY@59..60 "}"
"#
.trim()
);
}
#[test]
fn test_syntax_tree_with_range() {
let (analysis, range) = fixture::range(r#"<|>fn foo() {}<|>"#.trim());
let syn = analysis.syntax_tree(range.file_id, Some(range.range)).unwrap();
assert_eq_text!(
syn.trim(),
r#"
FN@0..11
FN_KW@0..2 "fn"
WHITESPACE@2..3 " "
NAME@3..6
IDENT@3..6 "foo"
PARAM_LIST@6..8
L_PAREN@6..7 "("
R_PAREN@7..8 ")"
WHITESPACE@8..9 " "
BLOCK_EXPR@9..11
L_CURLY@9..10 "{"
R_CURLY@10..11 "}"
"#
.trim()
);
let (analysis, range) = fixture::range(
r#"fn test() {
<|>assert!("
fn foo() {
}
", "");<|>
}"#
.trim(),
);
let syn = analysis.syntax_tree(range.file_id, Some(range.range)).unwrap();
assert_eq_text!(
syn.trim(),
r#"
EXPR_STMT@16..58
MACRO_CALL@16..57
PATH@16..22
PATH_SEGMENT@16..22
NAME_REF@16..22
IDENT@16..22 "assert"
BANG@22..23 "!"
TOKEN_TREE@23..57
L_PAREN@23..24 "("
STRING@24..52 "\"\n fn foo() {\n ..."
COMMA@52..53 ","
WHITESPACE@53..54 " "
STRING@54..56 "\"\""
R_PAREN@56..57 ")"
SEMICOLON@57..58 ";"
"#
.trim()
);
}
#[test]
fn test_syntax_tree_inside_string() {
let (analysis, range) = fixture::range(
r#"fn test() {
assert!("
<|>fn foo() {
}<|>
fn bar() {
}
", "");
}"#
.trim(),
);
let syn = analysis.syntax_tree(range.file_id, Some(range.range)).unwrap();
assert_eq_text!(
syn.trim(),
r#"
SOURCE_FILE@0..12
FN@0..12
FN_KW@0..2 "fn"
WHITESPACE@2..3 " "
NAME@3..6
IDENT@3..6 "foo"
PARAM_LIST@6..8
L_PAREN@6..7 "("
R_PAREN@7..8 ")"
WHITESPACE@8..9 " "
BLOCK_EXPR@9..12
L_CURLY@9..10 "{"
WHITESPACE@10..11 "\n"
R_CURLY@11..12 "}"
"#
.trim()
);
// With a raw string
let (analysis, range) = fixture::range(
r###"fn test() {
assert!(r#"
<|>fn foo() {
}<|>
fn bar() {
}
"#, "");
}"###
.trim(),
);
let syn = analysis.syntax_tree(range.file_id, Some(range.range)).unwrap();
assert_eq_text!(
syn.trim(),
r#"
SOURCE_FILE@0..12
FN@0..12
FN_KW@0..2 "fn"
WHITESPACE@2..3 " "
NAME@3..6
IDENT@3..6 "foo"
PARAM_LIST@6..8
L_PAREN@6..7 "("
R_PAREN@7..8 ")"
WHITESPACE@8..9 " "
BLOCK_EXPR@9..12
L_CURLY@9..10 "{"
WHITESPACE@10..11 "\n"
R_CURLY@11..12 "}"
"#
.trim()
);
// With a raw string
let (analysis, range) = fixture::range(
r###"fn test() {
assert!(r<|>#"
fn foo() {
}
fn bar() {
}"<|>#, "");
}"###
.trim(),
);
let syn = analysis.syntax_tree(range.file_id, Some(range.range)).unwrap();
assert_eq_text!(
syn.trim(),
r#"
SOURCE_FILE@0..25
FN@0..12
FN_KW@0..2 "fn"
WHITESPACE@2..3 " "
NAME@3..6
IDENT@3..6 "foo"
PARAM_LIST@6..8
L_PAREN@6..7 "("
R_PAREN@7..8 ")"
WHITESPACE@8..9 " "
BLOCK_EXPR@9..12
L_CURLY@9..10 "{"
WHITESPACE@10..11 "\n"
R_CURLY@11..12 "}"
WHITESPACE@12..13 "\n"
FN@13..25
FN_KW@13..15 "fn"
WHITESPACE@15..16 " "
NAME@16..19
IDENT@16..19 "bar"
PARAM_LIST@19..21
L_PAREN@19..20 "("
R_PAREN@20..21 ")"
WHITESPACE@21..22 " "
BLOCK_EXPR@22..25
L_CURLY@22..23 "{"
WHITESPACE@23..24 "\n"
R_CURLY@24..25 "}"
"#
.trim()
);
}
}
|