47 releases

new 0.0.61 Jun 21, 2021
0.0.58 May 31, 2021
0.0.44 Mar 29, 2021
0.0.30 Dec 28, 2020
0.0.26 Nov 30, 2020
Download history 2320/week @ 2021-02-26 1890/week @ 2021-03-05 2081/week @ 2021-03-12 778/week @ 2021-03-19 685/week @ 2021-03-26 713/week @ 2021-04-02 955/week @ 2021-04-09 1086/week @ 2021-04-16 695/week @ 2021-04-23 644/week @ 2021-04-30 496/week @ 2021-05-07 742/week @ 2021-05-14 685/week @ 2021-05-21 1132/week @ 2021-05-28 930/week @ 2021-06-04 821/week @ 2021-06-11

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Used in 26 crates (5 directly)


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Virtual File System

VFS stores all files read by rust-analyzer. Reading file contents from VFS always returns the same contents, unless VFS was explicitly modified with set_file_contents. All changes to VFS are logged, and can be retrieved via take_changes method. The pack of changes is then pushed to salsa and triggers incremental recomputation.

Files in VFS are identified with [FileId]s -- interned paths. The notion of the path, [VfsPath] is somewhat abstract: at the moment, it is represented as an [std::path::PathBuf] internally, but this is an implementation detail.

VFS doesn't do IO or file watching itself. For that, see the [loader] module. [loader::Handle] is an object-safe trait which abstracts both file loading and file watching. Handle is dynamically configured with a set of directory entries which should be scanned and watched. Handle then asynchronously pushes file changes. Directory entries are configured in free-form via list of globs, it's up to the Handle to interpret the globs in any specific way.

VFS stores a flat list of files. [file_set::FileSet] can partition this list of files into disjoint sets of files. Traversal-like operations (including getting the neighbor file by the relative path) are handled by the FileSet. FileSets are also pushed to salsa and cause it to re-check mod foo; declarations when files are created or deleted.

FileSet and [loader::Entry] play similar, but different roles. Both specify the "set of paths/files", one is geared towards file watching, the other towards salsa changes. In particular, single FileSet may correspond to several [loader::Entry]. For example, a crate from crates.io which uses code generation would have two Entries -- for sources in ~/.cargo, and for generated code in ./target/debug/build. It will have a single FileSet which unions the two sources.


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