1 files changed, 143 insertions, 0 deletions

diff --git a/crates/project_model/src/project_json.rs b/crates/project_model/src/project_json.rs
new file mode 100644
index 000000000..060ea5b7d
--- /dev/null
+++ b/crates/project_model/src/project_json.rs
@@ -0,0 +1,143 @@
+//! FIXME: write short doc here
+
+use std::path::PathBuf;
+
+use base_db::{CrateId, CrateName, Dependency, Edition};
+use paths::{AbsPath, AbsPathBuf};
+use rustc_hash::FxHashMap;
+use serde::{de, Deserialize};
+
+use crate::cfg_flag::CfgFlag;
+
+/// Roots and crates that compose this Rust project.
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct ProjectJson {
+    pub(crate) crates: Vec<Crate>,
+}
+
+/// A crate points to the root module of a crate and lists the dependencies of the crate. This is
+/// useful in creating the crate graph.
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct Crate {
+    pub(crate) root_module: AbsPathBuf,
+    pub(crate) edition: Edition,
+    pub(crate) deps: Vec<Dependency>,
+    pub(crate) cfg: Vec<CfgFlag>,
+    pub(crate) target: Option<String>,
+    pub(crate) env: FxHashMap<String, String>,
+    pub(crate) proc_macro_dylib_path: Option<AbsPathBuf>,
+    pub(crate) is_workspace_member: bool,
+    pub(crate) include: Vec<AbsPathBuf>,
+    pub(crate) exclude: Vec<AbsPathBuf>,
+}
+
+impl ProjectJson {
+    pub fn new(base: &AbsPath, data: ProjectJsonData) -> ProjectJson {
+        ProjectJson {
+            crates: data
+                .crates
+                .into_iter()
+                .map(|crate_data| {
+                    let is_workspace_member = crate_data.is_workspace_member.unwrap_or_else(|| {
+                        crate_data.root_module.is_relative()
+                            && !crate_data.root_module.starts_with("..")
+                            || crate_data.root_module.starts_with(base)
+                    });
+                    let root_module = base.join(crate_data.root_module);
+                    let (include, exclude) = match crate_data.source {
+                        Some(src) => {
+                            let absolutize = |dirs: Vec<PathBuf>| {
+                                dirs.into_iter().map(|it| base.join(it)).collect::<Vec<_>>()
+                            };
+                            (absolutize(src.include_dirs), absolutize(src.exclude_dirs))
+                        }
+                        None => (vec![root_module.parent().unwrap().to_path_buf()], Vec::new()),
+                    };
+
+                    Crate {
+                        root_module,
+                        edition: crate_data.edition.into(),
+                        deps: crate_data
+                            .deps
+                            .into_iter()
+                            .map(|dep_data| Dependency {
+                                crate_id: CrateId(dep_data.krate as u32),
+                                name: dep_data.name,
+                            })
+                            .collect::<Vec<_>>(),
+                        cfg: crate_data.cfg,
+                        target: crate_data.target,
+                        env: crate_data.env,
+                        proc_macro_dylib_path: crate_data
+                            .proc_macro_dylib_path
+                            .map(|it| base.join(it)),
+                        is_workspace_member,
+                        include,
+                        exclude,
+                    }
+                })
+                .collect::<Vec<_>>(),
+        }
+    }
+}
+
+#[derive(Deserialize)]
+pub struct ProjectJsonData {
+    crates: Vec<CrateData>,
+}
+
+#[derive(Deserialize)]
+struct CrateData {
+    root_module: PathBuf,
+    edition: EditionData,
+    deps: Vec<DepData>,
+    #[serde(default)]
+    cfg: Vec<CfgFlag>,
+    target: Option<String>,
+    #[serde(default)]
+    env: FxHashMap<String, String>,
+    proc_macro_dylib_path: Option<PathBuf>,
+    is_workspace_member: Option<bool>,
+    source: Option<CrateSource>,
+}
+
+#[derive(Deserialize)]
+#[serde(rename = "edition")]
+enum EditionData {
+    #[serde(rename = "2015")]
+    Edition2015,
+    #[serde(rename = "2018")]
+    Edition2018,
+}
+
+impl From<EditionData> for Edition {
+    fn from(data: EditionData) -> Self {
+        match data {
+            EditionData::Edition2015 => Edition::Edition2015,
+            EditionData::Edition2018 => Edition::Edition2018,
+        }
+    }
+}
+
+#[derive(Deserialize)]
+struct DepData {
+    /// Identifies a crate by position in the crates array.
+    #[serde(rename = "crate")]
+    krate: usize,
+    #[serde(deserialize_with = "deserialize_crate_name")]
+    name: CrateName,
+}
+
+#[derive(Deserialize)]
+struct CrateSource {
+    include_dirs: Vec<PathBuf>,
+    exclude_dirs: Vec<PathBuf>,
+}
+
+fn deserialize_crate_name<'de, D>(de: D) -> Result<CrateName, D::Error>
+where
+    D: de::Deserializer<'de>,
+{
+    let name = String::deserialize(de)?;
+    CrateName::new(&name).map_err(|err| de::Error::custom(format!("invalid crate name: {:?}", err)))
+}