Move crate graph generation to ra_project_model

crates/ra_project_model/src/lib.rs

@@ -4,6 +4,10 @@ mod sysroot;
 use std::path::{Path, PathBuf};
 
 use failure::bail;
+use rustc_hash::FxHashMap;
+
+use ra_db::{CrateGraph, FileId};
+use ra_vfs::Vfs;
 
 pub use crate::{
     cargo_workspace::{CargoWorkspace, Package, Target, TargetKind},
@@ -27,6 +31,90 @@ impl ProjectWorkspace {
         let res = ProjectWorkspace { cargo, sysroot };
         Ok(res)
     }
+
+    pub fn to_crate_graph(&self, vfs: &mut Vfs) -> CrateGraph {
+        let mut crate_graph = CrateGraph::default();
+        let mut sysroot_crates = FxHashMap::default();
+        for krate in self.sysroot.crates() {
+            if let Some(file_id) = vfs.load(krate.root(&self.sysroot)) {
+                let file_id = FileId(file_id.0.into());
+                sysroot_crates.insert(krate, crate_graph.add_crate_root(file_id));
+            }
+        }
+        for from in self.sysroot.crates() {
+            for to in from.deps(&self.sysroot) {
+                let name = to.name(&self.sysroot);
+                if let (Some(&from), Some(&to)) =
+                    (sysroot_crates.get(&from), sysroot_crates.get(&to))
+                {
+                    if let Err(_) = crate_graph.add_dep(from, name.clone(), to) {
+                        log::error!("cyclic dependency between sysroot crates")
+                    }
+                }
+            }
+        }
+
+        let libstd = self.sysroot.std().and_then(|it| sysroot_crates.get(&it).map(|&it| it));
+
+        let mut pkg_to_lib_crate = FxHashMap::default();
+        let mut pkg_crates = FxHashMap::default();
+        // Next, create crates for each package, target pair
+        for pkg in self.cargo.packages() {
+            let mut lib_tgt = None;
+            for tgt in pkg.targets(&self.cargo) {
+                let root = tgt.root(&self.cargo);
+                if let Some(file_id) = vfs.load(root) {
+                    let file_id = FileId(file_id.0.into());
+                    let crate_id = crate_graph.add_crate_root(file_id);
+                    if tgt.kind(&self.cargo) == TargetKind::Lib {
+                        lib_tgt = Some(crate_id);
+                        pkg_to_lib_crate.insert(pkg, crate_id);
+                    }
+                    pkg_crates.entry(pkg).or_insert_with(Vec::new).push(crate_id);
+                }
+            }
+
+            // Set deps to the std and to the lib target of the current package
+            for &from in pkg_crates.get(&pkg).into_iter().flatten() {
+                if let Some(to) = lib_tgt {
+                    if to != from {
+                        if let Err(_) = crate_graph.add_dep(from, pkg.name(&self.cargo).into(), to)
+                        {
+                            log::error!(
+                                "cyclic dependency between targets of {}",
+                                pkg.name(&self.cargo)
+                            )
+                        }
+                    }
+                }
+                if let Some(std) = libstd {
+                    if let Err(_) = crate_graph.add_dep(from, "std".into(), std) {
+                        log::error!("cyclic dependency on std for {}", pkg.name(&self.cargo))
+                    }
+                }
+            }
+        }
+
+        // Now add a dep ednge from all targets of upstream to the lib
+        // target of downstream.
+        for pkg in self.cargo.packages() {
+            for dep in pkg.dependencies(&self.cargo) {
+                if let Some(&to) = pkg_to_lib_crate.get(&dep.pkg) {
+                    for &from in pkg_crates.get(&pkg).into_iter().flatten() {
+                        if let Err(_) = crate_graph.add_dep(from, dep.name.clone(), to) {
+                            log::error!(
+                                "cyclic dependency {} -> {}",
+                                pkg.name(&self.cargo),
+                                dep.pkg.name(&self.cargo)
+                            )
+                        }
+                    }
+                }
+            }
+        }
+
+        crate_graph
+    }
 }
 
 fn find_cargo_toml(path: &Path) -> Result<PathBuf> {