1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
use swc_atoms::JsWord;
use swc_common::{
    comments::{Comment, SingleThreadedComments},
    Loc, SourceMap, Span, DUMMY_SP,
};
use swc_ecma_ast as ast;
use swc_ecma_visit::{self, Node, Visit, VisitWith};

pub fn analyze_dependencies(
    module: &ast::Module,
    source_map: &SourceMap,
    comments: &SingleThreadedComments,
) -> Vec<DependencyDescriptor> {
    let mut v = DependencyCollector {
        comments,
        source_map,
        items: vec![],
        is_top_level: true,
    };
    module.visit_with(&ast::Invalid { span: DUMMY_SP }, &mut v);
    v.items
}

#[derive(Clone, Debug, Eq, PartialEq)]
pub enum DependencyKind {
    Import,
    ImportType,
    Export,
    ExportType,
    Require,
}

#[derive(Clone, Debug, Eq, PartialEq)]
pub struct DependencyDescriptor {
    pub kind: DependencyKind,
    /// A flag indicating if the import is dynamic or not.
    pub is_dynamic: bool,
    /// Any leading comments associated with the dependency.  This is used for
    /// further processing of supported pragma that impact the dependency.
    pub leading_comments: Vec<Comment>,
    /// The location of the import/export statement.
    pub col: usize,
    pub line: usize,
    /// The text specifier associated with the import/export statement.
    pub specifier: JsWord,
}

struct DependencyCollector<'a> {
    comments: &'a SingleThreadedComments,
    pub items: Vec<DependencyDescriptor>,
    source_map: &'a SourceMap,
    // This field is used to determine if currently visited "require"
    // is top level and "static", or inside module body and "dynamic".
    is_top_level: bool,
}

impl<'a> DependencyCollector<'a> {
    fn get_location_and_comments(&self, span: Span) -> (Loc, Vec<Comment>) {
        let location = self.source_map.lookup_char_pos(span.lo);
        let leading_comments = self
            .comments
            .with_leading(span.lo, |comments| comments.to_vec());
        (location, leading_comments)
    }
}

impl<'a> Visit for DependencyCollector<'a> {
    fn visit_import_decl(&mut self, node: &ast::ImportDecl, _parent: &dyn Node) {
        let specifier = node.src.value.clone();
        let span = node.span;
        let (location, leading_comments) = self.get_location_and_comments(span);
        let kind = if node.type_only {
            DependencyKind::ImportType
        } else {
            DependencyKind::Import
        };
        self.items.push(DependencyDescriptor {
            kind,
            is_dynamic: false,
            leading_comments,
            col: location.col_display,
            line: location.line,
            specifier,
        });
    }

    fn visit_named_export(&mut self, node: &ast::NamedExport, _parent: &dyn Node) {
        if let Some(src) = &node.src {
            let specifier = src.value.clone();
            let span = node.span;
            let (location, leading_comments) = self.get_location_and_comments(span);
            let kind = if node.type_only {
                DependencyKind::ExportType
            } else {
                DependencyKind::Export
            };
            self.items.push(DependencyDescriptor {
                kind,
                is_dynamic: false,
                leading_comments,
                col: location.col_display,
                line: location.line,
                specifier,
            });
        }
    }

    fn visit_export_all(&mut self, node: &ast::ExportAll, _parent: &dyn Node) {
        let specifier = node.src.value.clone();
        let span = node.span;
        let (location, leading_comments) = self.get_location_and_comments(span);
        self.items.push(DependencyDescriptor {
            kind: DependencyKind::Export,
            is_dynamic: false,
            leading_comments,
            col: location.col_display,
            line: location.line,
            specifier,
        });
    }

    fn visit_ts_import_type(&mut self, node: &ast::TsImportType, _parent: &dyn Node) {
        let specifier = node.arg.value.clone();
        let span = node.span;
        let (location, leading_comments) = self.get_location_and_comments(span);
        self.items.push(DependencyDescriptor {
            kind: DependencyKind::ImportType,
            is_dynamic: false,
            leading_comments,
            col: location.col_display,
            line: location.line,
            specifier,
        });
    }

    fn visit_module_items(&mut self, items: &[ast::ModuleItem], _parent: &dyn Node) {
        swc_ecma_visit::visit_module_items(self, items, _parent);
    }

    fn visit_stmts(&mut self, items: &[ast::Stmt], _parent: &dyn Node) {
        self.is_top_level = false;
        swc_ecma_visit::visit_stmts(self, items, _parent);
        self.is_top_level = true;
    }

    fn visit_call_expr(&mut self, node: &ast::CallExpr, _parent: &dyn Node) {
        use ast::{Expr::*, ExprOrSuper::*};

        swc_ecma_visit::visit_call_expr(self, node, _parent);
        let call_expr = match node.callee.clone() {
            Super(_) => return,
            Expr(boxed) => boxed,
        };

        let kind = match &*call_expr {
            Ident(ident) => match ident.sym.to_string().as_str() {
                "import" => DependencyKind::Import,
                "require" => DependencyKind::Require,
                _ => return,
            },
            _ => return,
        };

        // import() are always dynamic, even if at top level
        let is_dynamic = !self.is_top_level || kind == DependencyKind::Import;

        if let Some(arg) = node.args.get(0) {
            if let Lit(lit) = &*arg.expr {
                if let ast::Lit::Str(str_) = lit {
                    let specifier = str_.value.clone();
                    let span = node.span;
                    let (location, leading_comments) = self.get_location_and_comments(span);
                    self.items.push(DependencyDescriptor {
                        kind,
                        is_dynamic,
                        leading_comments,
                        col: location.col_display,
                        line: location.line,
                        specifier,
                    });
                }
            }
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use swc_common::{
        comments::{Comment, CommentKind},
        sync::Lrc,
        BytePos, FileName, Span, SyntaxContext,
    };
    use swc_ecma_parser::{lexer::Lexer, JscTarget, Parser, StringInput, Syntax, TsConfig};

    fn helper(
        file_name: &str,
        source: &str,
    ) -> Result<(ast::Module, Lrc<SourceMap>, SingleThreadedComments), testing::StdErr> {
        let output = ::testing::run_test(true, |cm, handler| {
            let fm =
                cm.new_source_file(FileName::Custom(file_name.to_string()), source.to_string());

            let comments = SingleThreadedComments::default();
            let lexer: Lexer<StringInput<'_>> = Lexer::new(
                Syntax::Typescript(TsConfig {
                    dts: file_name.ends_with(".d.ts"),
                    tsx: file_name.contains("tsx"),
                    dynamic_import: true,
                    decorators: true,
                    no_early_errors: true,
                    ..Default::default()
                }),
                JscTarget::Es2015,
                (&*fm).into(),
                Some(&comments),
            );

            let mut p = Parser::new_from(lexer);

            let res = p
                .parse_module()
                .map_err(|e| e.into_diagnostic(&handler).emit());

            for err in p.take_errors() {
                err.into_diagnostic(&handler).emit();
            }

            if handler.has_errors() {
                return Err(());
            }

            Ok((res.unwrap(), cm, comments))
        });

        output
    }

    #[test]
    fn test_parsed_module_get_dependencies() {
        let source = r#"import * as bar from "./test.ts";
/** JSDoc */
import type { Foo } from "./foo.d.ts";
/// <reference foo="bar" />
export * as Buzz from "./buzz.ts";
// @some-pragma
/**
 * Foo
 */
export type { Fizz } from "./fizz.d.ts";
const { join } = require("path");

// dynamic 
await import("./foo1.ts");

try {
    const foo = await import("./foo.ts");
} catch (e) {
    // pass
}

try {
    const foo = require("some_package");
} catch (e) {
    // pass
}
      "#;
        let (module, source_map, comments) = helper("test.ts", &source).unwrap();
        // eprintln!("module {:#?}", module);
        let dependencies = analyze_dependencies(&module, &source_map, &comments);
        assert_eq!(dependencies.len(), 8);
        assert_eq!(
            dependencies,
            vec![
                DependencyDescriptor {
                    kind: DependencyKind::Import,
                    is_dynamic: false,
                    leading_comments: Vec::new(),
                    col: 0,
                    line: 1,
                    specifier: JsWord::from("./test.ts")
                },
                DependencyDescriptor {
                    kind: DependencyKind::ImportType,
                    is_dynamic: false,
                    leading_comments: vec![Comment {
                        kind: CommentKind::Block,
                        text: r#"* JSDoc "#.to_string(),
                        span: Span::new(BytePos(34), BytePos(46), SyntaxContext::empty()),
                    }],
                    col: 0,
                    line: 3,
                    specifier: JsWord::from("./foo.d.ts")
                },
                DependencyDescriptor {
                    kind: DependencyKind::Export,
                    is_dynamic: false,
                    leading_comments: vec![Comment {
                        kind: CommentKind::Line,
                        text: r#"/ <reference foo="bar" />"#.to_string(),
                        span: Span::new(BytePos(86), BytePos(113), SyntaxContext::empty()),
                    }],
                    col: 0,
                    line: 5,
                    specifier: JsWord::from("./buzz.ts")
                },
                DependencyDescriptor {
                    kind: DependencyKind::ExportType,
                    is_dynamic: false,
                    leading_comments: vec![
                        Comment {
                            kind: CommentKind::Line,
                            text: r#" @some-pragma"#.to_string(),
                            span: Span::new(BytePos(149), BytePos(164), SyntaxContext::empty()),
                        },
                        Comment {
                            kind: CommentKind::Block,
                            text: "*\n * Foo\n ".to_string(),
                            span: Span::new(BytePos(165), BytePos(179), SyntaxContext::empty()),
                        }
                    ],
                    col: 0,
                    line: 10,
                    specifier: JsWord::from("./fizz.d.ts")
                },
                DependencyDescriptor {
                    kind: DependencyKind::Require,
                    is_dynamic: false,
                    leading_comments: Vec::new(),
                    col: 17,
                    line: 11,
                    specifier: JsWord::from("path")
                },
                DependencyDescriptor {
                    kind: DependencyKind::Import,
                    is_dynamic: true,
                    leading_comments: Vec::new(),
                    col: 6,
                    line: 14,
                    specifier: JsWord::from("./foo1.ts")
                },
                DependencyDescriptor {
                    kind: DependencyKind::Import,
                    is_dynamic: true,
                    leading_comments: Vec::new(),
                    col: 22,
                    line: 17,
                    specifier: JsWord::from("./foo.ts")
                },
                DependencyDescriptor {
                    kind: DependencyKind::Require,
                    is_dynamic: true,
                    leading_comments: Vec::new(),
                    col: 16,
                    line: 23,
                    specifier: JsWord::from("some_package")
                }
            ]
        );
    }
}