move fs (std) resolve functionality to resolve::fs and move resolve.rs to resolve/mod.rs

Author: wilfreddenton

crates/wit-parser/src/resolve/fs.rs

@@ -0,0 +1,272 @@
+//! Filesystem operations for [`Resolve`].
+
+use alloc::format;
+use alloc::string::ToString;
+use std::path::Path;
+use std::vec::Vec;
+
+use anyhow::{Context, Result, bail};
+
+use super::{PackageSources, Resolve};
+use crate::{IndexSet, UnresolvedPackageGroup};
+
+/// All the sources used during resolving a directory or path.
+#[derive(Clone, Debug)]
+pub struct PackageSourceMap {
+    inner: PackageSources,
+}
+
+impl PackageSourceMap {
+    pub(super) fn from_single_source(package_id: super::PackageId, source: &Path) -> Self {
+        use alloc::collections::BTreeMap;
+        use alloc::vec;
+
+        Self {
+            inner: PackageSources {
+                sources: vec![vec![source.display().to_string()]],
+                package_id_to_source_map_idx: BTreeMap::from([(package_id, 0)]),
+            },
+        }
+    }
+
+    pub(super) fn from_inner(inner: PackageSources) -> Self {
+        Self { inner }
+    }
+
+    /// All unique source paths.
+    pub fn paths(&self) -> impl Iterator<Item = &Path> {
+        // Usually any two source map should not have duplicated source paths,
+        // but it can happen, e.g. with using [`Resolve::push_str`] directly.
+        // To be sure we use a set for deduplication here.
+        self.inner
+            .sources
+            .iter()
+            .flatten()
+            .map(|s| Path::new(s))
+            .collect::<IndexSet<&Path>>()
+            .into_iter()
+    }
+
+    /// Source paths for package
+    pub fn package_paths(&self, id: super::PackageId) -> Option<impl Iterator<Item = &Path>> {
+        self.inner
+            .package_id_to_source_map_idx
+            .get(&id)
+            .map(|&idx| self.inner.sources[idx].iter().map(|s| Path::new(s)))
+    }
+}
+
+enum ParsedFile {
+    #[cfg(feature = "decoding")]
+    Package(super::PackageId),
+    Unresolved(UnresolvedPackageGroup),
+}
+
+impl Resolve {
+    /// Parse WIT packages from the input `path`.
+    ///
+    /// The input `path` can be one of:
+    ///
+    /// * A directory containing a WIT package with an optional `deps` directory
+    ///   for local dependencies. In this case `deps` is parsed first and then
+    ///   the parent `path` is parsed and returned.
+    /// * A single standalone WIT file.
+    /// * A wasm-encoded WIT package as a single file in either the text or
+    ///   binary format.
+    ///
+    /// More information can also be found at [`Resolve::push_dir`] and
+    /// [`Resolve::push_file`].
+    pub fn push_path(
+        &mut self,
+        path: impl AsRef<Path>,
+    ) -> Result<(super::PackageId, PackageSourceMap)> {
+        self._push_path(path.as_ref())
+    }
+
+    fn _push_path(&mut self, path: &Path) -> Result<(super::PackageId, PackageSourceMap)> {
+        if path.is_dir() {
+            self.push_dir(path).with_context(|| {
+                format!(
+                    "failed to resolve directory while parsing WIT for path [{}]",
+                    path.display()
+                )
+            })
+        } else {
+            let id = self.push_file(path)?;
+            Ok((id, PackageSourceMap::from_single_source(id, path)))
+        }
+    }
+
+    /// Parses the filesystem directory at `path` as a WIT package and returns
+    /// a fully resolved [`PackageId`] list as a result.
+    ///
+    /// The directory itself is parsed with [`UnresolvedPackageGroup::parse_dir`]
+    /// and then all packages found are inserted into this `Resolve`. The `path`
+    /// specified may have a `deps` subdirectory which is probed automatically
+    /// for any other WIT dependencies.
+    ///
+    /// The `deps` folder may contain:
+    ///
+    /// * `$path/deps/my-package/*.wit` - a directory that may contain multiple
+    ///   WIT files. This is parsed with [`UnresolvedPackageGroup::parse_dir`]
+    ///   and then inserted into this [`Resolve`]. Note that cannot recursively
+    ///   contain a `deps` directory.
+    /// * `$path/deps/my-package.wit` - a single-file WIT package. This is
+    ///   parsed with [`Resolve::push_file`] and then added to `self` for
+    ///   name resolution.
+    /// * `$path/deps/my-package.{wasm,wat}` - a wasm-encoded WIT package either
+    ///   in the text for binary format.
+    ///
+    /// In all cases entries in the `deps` folder are added to `self` first
+    /// before adding files found in `path` itself. All WIT packages found are
+    /// candidates for name-based resolution that other packages may use.
+    ///
+    /// This function returns a tuple of two values. The first value is a
+    /// [`PackageId`], which represents the main WIT package found within
+    /// `path`. This argument is useful for passing to [`Resolve::select_world`]
+    /// for choosing something to bindgen with.
+    ///
+    /// The second value returned is a [`PackageSourceMap`], which contains all the sources
+    /// that were parsed during resolving. This can be useful for:
+    /// * build systems that want to rebuild bindings whenever one of the files changed
+    /// * or other tools, which want to identify the sources for the resolved packages
+    pub fn push_dir(
+        &mut self,
+        path: impl AsRef<Path>,
+    ) -> Result<(super::PackageId, PackageSourceMap)> {
+        self._push_dir(path.as_ref())
+    }
+
+    fn _push_dir(&mut self, path: &Path) -> Result<(super::PackageId, PackageSourceMap)> {
+        let top_pkg = UnresolvedPackageGroup::parse_dir(path)
+            .with_context(|| format!("failed to parse package: {}", path.display()))?;
+        let deps = path.join("deps");
+        let deps = self
+            .parse_deps_dir(&deps)
+            .with_context(|| format!("failed to parse dependency directory: {}", deps.display()))?;
+
+        let (pkg_id, inner) = self.sort_unresolved_packages(top_pkg, deps)?;
+        Ok((pkg_id, PackageSourceMap::from_inner(inner)))
+    }
+
+    fn parse_deps_dir(&mut self, path: &Path) -> Result<Vec<UnresolvedPackageGroup>> {
+        let mut ret = Vec::new();
+        if !path.exists() {
+            return Ok(ret);
+        }
+        let mut entries = path
+            .read_dir()
+            .and_then(|i| i.collect::<std::io::Result<Vec<_>>>())
+            .context("failed to read directory")?;
+        entries.sort_by_key(|e| e.file_name());
+        for dep in entries {
+            let path = dep.path();
+            let pkg = if dep.file_type()?.is_dir() || path.metadata()?.is_dir() {
+                // If this entry is a directory or a symlink point to a
+                // directory then always parse it as an `UnresolvedPackage`
+                // since it's intentional to not support recursive `deps`
+                // directories.
+                UnresolvedPackageGroup::parse_dir(&path)
+                    .with_context(|| format!("failed to parse package: {}", path.display()))?
+            } else {
+                // If this entry is a file then we may want to ignore it but
+                // this may also be a standalone WIT file or a `*.wasm` or
+                // `*.wat` encoded package.
+                let filename = dep.file_name();
+                match Path::new(&filename).extension().and_then(|s| s.to_str()) {
+                    Some("wit") | Some("wat") | Some("wasm") => match self._push_file(&path)? {
+                        #[cfg(feature = "decoding")]
+                        ParsedFile::Package(_) => continue,
+                        ParsedFile::Unresolved(pkg) => pkg,
+                    },
+
+                    // Other files in deps dir are ignored for now to avoid
+                    // accidentally including things like `.DS_Store` files in
+                    // the call below to `parse_dir`.
+                    _ => continue,
+                }
+            };
+            ret.push(pkg);
+        }
+        Ok(ret)
+    }
+
+    /// Parses the contents of `path` from the filesystem and pushes the result
+    /// into this `Resolve`.
+    ///
+    /// The `path` referenced here can be one of:
+    ///
+    /// * A WIT file. Note that in this case this single WIT file will be the
+    ///   entire package and any dependencies it has must already be in `self`.
+    /// * A WIT package encoded as WebAssembly, either in text or binary form.
+    ///   In this the package and all of its dependencies are automatically
+    ///   inserted into `self`.
+    ///
+    /// In both situations the `PackageId`s of the resulting resolved packages
+    /// are returned from this method. The return value is mostly useful in
+    /// conjunction with [`Resolve::select_world`].
+    pub fn push_file(&mut self, path: impl AsRef<Path>) -> Result<super::PackageId> {
+        match self._push_file(path.as_ref())? {
+            #[cfg(feature = "decoding")]
+            ParsedFile::Package(id) => Ok(id),
+            ParsedFile::Unresolved(pkg) => self.push_group(pkg),
+        }
+    }
+
+    fn _push_file(&mut self, path: &Path) -> Result<ParsedFile> {
+        let contents = std::fs::read(path)
+            .with_context(|| format!("failed to read path for WIT [{}]", path.display()))?;
+
+        // If decoding is enabled at compile time then try to see if this is a
+        // wasm file.
+        #[cfg(feature = "decoding")]
+        {
+            use crate::decoding::{DecodedWasm, decode};
+
+            #[cfg(feature = "wat")]
+            let is_wasm = wat::Detect::from_bytes(&contents).is_wasm();
+            #[cfg(not(feature = "wat"))]
+            let is_wasm = wasmparser::Parser::is_component(&contents);
+
+            if is_wasm {
+                #[cfg(feature = "wat")]
+                let contents = wat::parse_bytes(&contents).map_err(|mut e| {
+                    e.set_path(path);
+                    e
+                })?;
+
+                match decode(&contents)? {
+                    DecodedWasm::Component(..) => {
+                        bail!("found an actual component instead of an encoded WIT package in wasm")
+                    }
+                    DecodedWasm::WitPackage(resolve, pkg) => {
+                        let remap = self.merge(resolve)?;
+                        return Ok(ParsedFile::Package(remap.packages[pkg.index()]));
+                    }
+                }
+            }
+        }
+
+        // If this wasn't a wasm file then assume it's a WIT file.
+        let text = match core::str::from_utf8(&contents) {
+            Ok(s) => s,
+            Err(_) => bail!("input file is not valid utf-8 [{}]", path.display()),
+        };
+        let pkgs = UnresolvedPackageGroup::parse(path, text)?;
+        Ok(ParsedFile::Unresolved(pkgs))
+    }
+
+    /// Convenience method for combining [`UnresolvedPackageGroup::parse`] and
+    /// [`Resolve::push_group`].
+    ///
+    /// The `path` provided is used for error messages but otherwise is not
+    /// read. This method does not touch the filesystem. The `contents` provided
+    /// are the contents of a WIT package.
+    pub fn push_str(&mut self, path: impl AsRef<Path>, contents: &str) -> Result<super::PackageId> {
+        let path = path
+            .as_ref()
+            .to_str()
+            .ok_or_else(|| anyhow::anyhow!("path is not valid utf-8: {:?}", path.as_ref()))?;
+        self.push_source(path, contents)
+    }
+}