Move keymap_file module into settings crate

Co-authored-by: Keith Simmons <keith@zed.dev

crates/settings/src/keymap_file.rs

@@ -0,0 +1,43 @@
+use anyhow::{Context, Result};
+use collections::BTreeMap;
+use gpui::{keymap::Binding, MutableAppContext};
+use serde::Deserialize;
+use serde_json::value::RawValue;
+
+#[derive(Deserialize)]
+struct ActionWithData<'a>(#[serde(borrow)] &'a str, #[serde(borrow)] &'a RawValue);
+type ActionSetsByContext<'a> = BTreeMap<&'a str, ActionsByKeystroke<'a>>;
+type ActionsByKeystroke<'a> = BTreeMap<&'a str, &'a RawValue>;
+
+pub fn load_keymap(cx: &mut MutableAppContext, content: &str) -> Result<()> {
+    let actions: ActionSetsByContext = serde_json::from_str(content)?;
+    for (context, actions) in actions {
+        let context = if context.is_empty() {
+            None
+        } else {
+            Some(context)
+        };
+        cx.add_bindings(
+            actions
+                .into_iter()
+                .map(|(keystroke, action)| {
+                    let action = action.get();
+                    let action = if action.starts_with('[') {
+                        let ActionWithData(name, data) = serde_json::from_str(action)?;
+                        cx.deserialize_action(name, Some(data.get()))
+                    } else {
+                        let name = serde_json::from_str(action)?;
+                        cx.deserialize_action(name, None)
+                    }
+                    .with_context(|| {
+                        format!(
+                            "invalid binding value for keystroke {keystroke}, context {context:?}"
+                        )
+                    })?;
+                    Binding::load(keystroke, action, context)
+                })
+                .collect::<Result<Vec<_>>>()?,
+        )
+    }
+    Ok(())
+}