internal: make sure that proc macro machinery doesn't depend on cwd

Cargo.lock

@@ -1042,6 +1042,9 @@ dependencies = [
 [[package]]
 name = "paths"
 version = "0.0.0"
+dependencies = [
+ "serde",
+]
 
 [[package]]
 name = "percent-encoding"
@@ -1109,6 +1112,7 @@ dependencies = [
  "log",
  "memmap2",
  "object",
+ "paths",
  "profile",
  "serde",
  "serde_json",

crates/paths/Cargo.toml

@@ -7,3 +7,6 @@ edition = "2018"
 
 [lib]
 doctest = false
+
+[dependencies]
+serde = "1"

crates/paths/src/lib.rs

@@ -66,6 +66,27 @@ impl PartialEq<AbsPath> for AbsPathBuf {
     }
 }
 
+impl serde::Serialize for AbsPathBuf {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        self.0.serialize(serializer)
+    }
+}
+
+impl<'de> serde::Deserialize<'de> for AbsPathBuf {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        let path = PathBuf::deserialize(deserializer)?;
+        AbsPathBuf::try_from(path).map_err(|path| {
+            serde::de::Error::custom(format!("expected absolute path, got {}", path.display()))
+        })
+    }
+}
+
 impl AbsPathBuf {
     /// Wrap the given absolute path in `AbsPathBuf`
     ///

crates/proc_macro_api/Cargo.toml

@@ -18,6 +18,7 @@ memmap2 = "0.3.0"
 object = { version = "0.25.3", default-features = false, features = ["std", "read_core", "elf", "macho", "pe"] }
 snap = "1.0"
 
+paths = { path = "../paths", version = "0.0.0" }
 tt = { path = "../tt", version = "0.0.0" }
 base_db = { path = "../base_db", version = "0.0.0" }
 stdx = { path = "../stdx", version = "0.0.0" }

crates/proc_macro_api/src/lib.rs

@@ -11,10 +11,10 @@ mod rpc;
 mod version;
 
 use base_db::{Env, ProcMacro};
+use paths::{AbsPath, AbsPathBuf};
 use std::{
     ffi::OsStr,
     io,
-    path::{Path, PathBuf},
     sync::{Arc, Mutex},
 };
 
@@ -28,7 +28,7 @@ pub use version::{read_dylib_info, RustCInfo};
 #[derive(Debug, Clone)]
 struct ProcMacroProcessExpander {
     process: Arc<Mutex<ProcMacroProcessSrv>>,
-    dylib_path: PathBuf,
+    dylib_path: AbsPathBuf,
     name: SmolStr,
 }
 
@@ -79,26 +79,25 @@ pub struct ProcMacroClient {
 impl ProcMacroClient {
     /// Spawns an external process as the proc macro server and returns a client connected to it.
     pub fn extern_process(
-        process_path: PathBuf,
+        process_path: AbsPathBuf,
         args: impl IntoIterator<Item = impl AsRef<OsStr>>,
     ) -> io::Result<ProcMacroClient> {
         let process = ProcMacroProcessSrv::run(process_path, args)?;
         Ok(ProcMacroClient { process: Arc::new(Mutex::new(process)) })
     }
 
-    // TODO: use paths::AbsPath here
-    pub fn by_dylib_path(&self, dylib_path: &Path) -> Vec<ProcMacro> {
+    pub fn by_dylib_path(&self, dylib_path: &AbsPath) -> Vec<ProcMacro> {
         let _p = profile::span("ProcMacroClient::by_dylib_path");
         match version::read_dylib_info(dylib_path) {
             Ok(info) => {
                 if info.version.0 < 1 || info.version.1 < 47 {
-                    eprintln!("proc-macro {} built by {:#?} is not supported by Rust Analyzer, please update your rust version.", dylib_path.to_string_lossy(), info);
+                    eprintln!("proc-macro {} built by {:#?} is not supported by Rust Analyzer, please update your rust version.", dylib_path.display(), info);
                 }
             }
             Err(err) => {
                 eprintln!(
                     "proc-macro {} failed to find the given version. Reason: {}",
-                    dylib_path.to_string_lossy(),
+                    dylib_path.display(),
                     err
                 );
             }
@@ -129,7 +128,7 @@ impl ProcMacroClient {
                 let expander = Arc::new(ProcMacroProcessExpander {
                     process: self.process.clone(),
                     name: name.clone(),
-                    dylib_path: dylib_path.into(),
+                    dylib_path: dylib_path.to_path_buf(),
                 });
 
                 ProcMacro { name, kind, expander }

crates/proc_macro_api/src/process.rs

@@ -4,10 +4,10 @@ use std::{
     convert::{TryFrom, TryInto},
     ffi::{OsStr, OsString},
     io::{self, BufRead, BufReader, Write},
-    path::{Path, PathBuf},
     process::{Child, ChildStdin, ChildStdout, Command, Stdio},
 };
 
+use paths::{AbsPath, AbsPathBuf};
 use stdx::JodChild;
 
 use crate::{
@@ -24,7 +24,7 @@ pub(crate) struct ProcMacroProcessSrv {
 
 impl ProcMacroProcessSrv {
     pub(crate) fn run(
-        process_path: PathBuf,
+        process_path: AbsPathBuf,
         args: impl IntoIterator<Item = impl AsRef<OsStr>>,
     ) -> io::Result<ProcMacroProcessSrv> {
         let mut process = Process::run(process_path, args)?;
@@ -37,7 +37,7 @@ impl ProcMacroProcessSrv {
 
     pub(crate) fn find_proc_macros(
         &mut self,
-        dylib_path: &Path,
+        dylib_path: &AbsPath,
     ) -> Result<Vec<(String, ProcMacroKind)>, tt::ExpansionError> {
         let task = ListMacrosTask { lib: dylib_path.to_path_buf() };
 
@@ -84,7 +84,7 @@ struct Process {
 
 impl Process {
     fn run(
-        path: PathBuf,
+        path: AbsPathBuf,
         args: impl IntoIterator<Item = impl AsRef<OsStr>>,
     ) -> io::Result<Process> {
         let args: Vec<OsString> = args.into_iter().map(|s| s.as_ref().into()).collect();
@@ -101,8 +101,11 @@ impl Process {
     }
 }
 
-fn mk_child(path: &Path, args: impl IntoIterator<Item = impl AsRef<OsStr>>) -> io::Result<Child> {
-    Command::new(&path)
+fn mk_child(
+    path: &AbsPath,
+    args: impl IntoIterator<Item = impl AsRef<OsStr>>,
+) -> io::Result<Child> {
+    Command::new(path.as_os_str())
         .args(args)
         .stdin(Stdio::piped())
         .stdout(Stdio::piped())

crates/proc_macro_api/src/rpc.rs

@@ -6,8 +6,7 @@
 //! to be much easier, we deliberately duplicate `tt` structs with `#[serde(with = "XXDef")]`
 //! for separation of code responsibility.
 
-use std::path::PathBuf;
-
+use paths::AbsPathBuf;
 use serde::{Deserialize, Serialize};
 use tt::{
     Delimiter, DelimiterKind, Ident, Leaf, Literal, Punct, SmolStr, Spacing, Subtree, TokenId,
@@ -16,7 +15,7 @@ use tt::{
 
 #[derive(Clone, Eq, PartialEq, Debug, Serialize, Deserialize)]
 pub struct ListMacrosTask {
-    pub lib: PathBuf,
+    pub lib: AbsPathBuf,
 }
 
 #[derive(Copy, Clone, Eq, PartialEq, Debug, Serialize, Deserialize)]
@@ -50,7 +49,7 @@ pub struct ExpansionTask {
     #[serde(with = "opt_subtree_def")]
     pub attributes: Option<Subtree>,
 
-    pub lib: PathBuf,
+    pub lib: AbsPathBuf,
 
     /// Environment variables to set during macro expansion.
     pub env: Vec<(String, String)>,

crates/proc_macro_api/src/version.rs

@@ -3,11 +3,11 @@
 use std::{
     fs::File,
     io::{self, Read},
-    path::Path,
 };
 
 use memmap2::Mmap;
 use object::read::{File as BinaryFile, Object, ObjectSection};
+use paths::AbsPath;
 use snap::read::FrameDecoder as SnapDecoder;
 
 #[derive(Debug)]
@@ -19,7 +19,7 @@ pub struct RustCInfo {
 }
 
 /// Read rustc dylib information
-pub fn read_dylib_info(dylib_path: &Path) -> io::Result<RustCInfo> {
+pub fn read_dylib_info(dylib_path: &AbsPath) -> io::Result<RustCInfo> {
     macro_rules! err {
         ($e:literal) => {
             io::Error::new(io::ErrorKind::InvalidData, $e)
@@ -96,7 +96,7 @@ fn read_section<'a>(dylib_binary: &'a [u8], section_name: &str) -> io::Result<&'
 /// * [some more bytes that we don really care but still there] :-)
 /// Check this issue for more about the bytes layout:
 /// <https://github.com/rust-analyzer/rust-analyzer/issues/6174>
-fn read_version(dylib_path: &Path) -> io::Result<String> {
+fn read_version(dylib_path: &AbsPath) -> io::Result<String> {
     let dylib_file = File::open(dylib_path)?;
     let dylib_mmaped = unsafe { Mmap::map(&dylib_file) }?;
 

crates/project_model/src/workspace.rs

@@ -312,7 +312,7 @@ impl ProjectWorkspace {
     ) -> CrateGraph {
         let _p = profile::span("ProjectWorkspace::to_crate_graph");
         let proc_macro_loader = |path: &AbsPath| match proc_macro_client {
-            Some(client) => client.by_dylib_path(path.as_ref()), // TODO
+            Some(client) => client.by_dylib_path(path),
             None => Vec::new(),
         };