Why are there duplicate import specifiers in TransformedModule?

[tmpfs]

I am writing a simple tool to walk the module graph and I noticed that on some occasions import specifiers are repeated multiple times for a single call to require().

A good example is importing react which yields this tree:

test/fixtures/basic-tree/main.js
└── react (1)
    └── ./cjs/react.development.js (2)
        ├── object-assign (3)
        ├── object-assign (3)
        └── object-assign (3)

The struct looks like this:

Imports {
    specifiers: [
        (
            Source {
                is_loaded_synchronously: true,
                is_unconditional: false,
                module_id: ModuleId(3),
                local_ctxt: #117,
                export_ctxt: #118,
                src: Str {
                    span: Span {
                        lo: BytePos(
                            675,
                        ),
                        hi: BytePos(
                            690,
                        ),
                        ctxt: #0,
                    },
                    value: Atom('object-assign' type=dynamic),
                    has_escape: false,
                    kind: Normal {
                        contains_quote: true,
                    },
                },
            },
            [],
        ),
        (
            Source {
                is_loaded_synchronously: true,
                is_unconditional: false,
                module_id: ModuleId(3),
                local_ctxt: #117,
                export_ctxt: #118,
                src: Str {
                    span: Span {
                        lo: BytePos(
                            675,
                        ),
                        hi: BytePos(
                            690,
                        ),
                        ctxt: #0,
                    },
                    value: Atom('object-assign' type=dynamic),
                    has_escape: false,
                    kind: Normal {
                        contains_quote: true,
                    },
                },
            },
            [
                Specific {
                    local: _assign#11,
                    alias: None,
                },
            ],
        ),
        (
            Source {
                is_loaded_synchronously: true,
                is_unconditional: false,
                module_id: ModuleId(3),
                local_ctxt: #117,
                export_ctxt: #118,
                src: Str {
                    span: Span {
                        lo: BytePos(
                            675,
                        ),
                        hi: BytePos(
                            690,
                        ),
                        ctxt: #0,
                    },
                    value: Atom('object-assign' type=dynamic),
                    has_escape: false,
                    kind: Normal {
                        contains_quote: true,
                    },
                },
            },
            [
                Specific {
                    local: _assign#11,
                    alias: None,
                },
            ],
        ),
    ],
}

When i inspect react/cjs/react.development.js there is only a single call to require().

I would expect only a single entry in the import specifiers. Is this a bug or do I misunderstand this data structure?

[kdy1]

Are you using rust?
If so, can you tell me which crate are you using?

I don't know well about swc_ecma_dep_graph (I didn't write and the bundler uses its own dependency analyzer because of deglobbing), but I can take a look.

[tmpfs]

Yes, I am using rust and building against source. I modified TransformedModule and it's nested structs to be public (I think these should be exposed from swc_bundler for this type of analysis - but that is a separate issue).

I am creating a Compiler and Bundler and calling load_transformed() to get the module data and was surprised to see these duplicates.

[kdy1]

Oh, it seems like a bug then.
I wasn't aware of it. Thanks!