variable refactor: completion also for magic vars

1 files changed, 70 insertions, 0 deletions

diff --git a/src/run/var.rs b/src/run/var.rs
new file mode 100644
index 0000000..0e64ad7
--- /dev/null
+++ b/src/run/var.rs
@@ -0,0 +1,70 @@
+use std::collections::{HashMap, HashSet};
+
+use crate::BString;
+use crate::bstr;
+
+pub struct Vars {
+    simple: HashMap<BString, BString>,
+    magic: HashMap<BString, fn() -> BString>,
+    all: HashSet<BString>,
+}
+
+impl Vars {
+    fn new(
+        mut simple: HashMap<BString, BString>,
+        magic: HashMap<BString, fn() -> BString>,
+    ) -> Self {
+        for (var, val) in std::env::vars_os() {
+            simple.insert(var.into_encoded_bytes(), val.into_encoded_bytes());
+        }
+        let all = simple
+            .keys()
+            .cloned()
+            .chain(magic.keys().cloned())
+            .collect();
+        Self { simple, magic, all }
+    }
+
+    pub fn set(&mut self, var: BString, val: BString) {
+        self.simple.insert(var.clone(), val);
+        self.all.insert(var);
+    }
+
+    pub fn lookup(&self, var: &bstr) -> Option<BString> {
+        if let Some(fun) = self.magic.get(var) {
+            return Some(fun());
+        }
+
+        if let Some(val) = self.simple.get(var) {
+            return Some(val.clone());
+        }
+
+        None
+    }
+
+    pub fn vars(&self) -> &HashSet<BString> {
+        &self.all
+    }
+}
+
+macro_rules! map {
+    ($($key:expr => $val:expr),* $(,)?) => {{
+        let mut map = HashMap::<BString, _, _>::new();
+        $(map.insert($key.into(), $val);)*
+        map
+    }};
+}
+
+impl Default for Vars {
+    fn default() -> Self {
+        let simple = map! {
+            b"PISH_VERSION" => crate::consts::PISH_VERSION.as_bytes().to_vec(),
+            b"PISH_COMMIT" => crate::consts::PISH_COMMIT.as_bytes().to_vec(),
+            b"PISH_DIRTY" => vec![crate::consts::PISH_DIRTY as u8 + b'0'],
+        };
+        let magic = map! {
+            b"CWD_PRETTY" => crate::pretty_cwd as _
+        };
+        Self::new(simple, magic)
+    }
+}