keymap_file.rs

  1use crate::{settings_store::parse_json_with_comments, SettingsAssets};
  2use anyhow::{anyhow, Context, Result};
  3use collections::{BTreeMap, HashMap};
  4use gpui::{Action, AppContext, KeyBinding, SharedString};
  5use schemars::{
  6    gen::SchemaGenerator,
  7    schema::{ArrayValidation, InstanceType, Metadata, Schema, SchemaObject, SubschemaValidation},
  8    JsonSchema,
  9};
 10use serde::Deserialize;
 11use serde_json::Value;
 12use util::{asset_str, ResultExt};
 13
 14#[derive(Debug, Deserialize, Default, Clone, JsonSchema)]
 15#[serde(transparent)]
 16pub struct KeymapFile(Vec<KeymapBlock>);
 17
 18#[derive(Debug, Deserialize, Default, Clone, JsonSchema)]
 19pub struct KeymapBlock {
 20    #[serde(default)]
 21    context: Option<String>,
 22    #[serde(default)]
 23    use_key_equivalents: Option<bool>,
 24    bindings: BTreeMap<String, KeymapAction>,
 25}
 26
 27impl KeymapBlock {
 28    pub fn context(&self) -> Option<&str> {
 29        self.context.as_deref()
 30    }
 31
 32    pub fn bindings(&self) -> &BTreeMap<String, KeymapAction> {
 33        &self.bindings
 34    }
 35}
 36
 37#[derive(Debug, Deserialize, Default, Clone)]
 38#[serde(transparent)]
 39pub struct KeymapAction(Value);
 40
 41impl std::fmt::Display for KeymapAction {
 42    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
 43        match &self.0 {
 44            Value::String(s) => write!(f, "{}", s),
 45            Value::Array(arr) => {
 46                let strings: Vec<String> = arr.iter().map(|v| v.to_string()).collect();
 47                write!(f, "{}", strings.join(", "))
 48            }
 49            _ => write!(f, "{}", self.0),
 50        }
 51    }
 52}
 53
 54impl JsonSchema for KeymapAction {
 55    fn schema_name() -> String {
 56        "KeymapAction".into()
 57    }
 58
 59    fn json_schema(_: &mut SchemaGenerator) -> Schema {
 60        Schema::Bool(true)
 61    }
 62}
 63
 64impl KeymapFile {
 65    pub fn load_asset(asset_path: &str, cx: &mut AppContext) -> Result<()> {
 66        let content = asset_str::<SettingsAssets>(asset_path);
 67
 68        Self::parse(content.as_ref())?.add_to_cx(cx)
 69    }
 70
 71    pub fn parse(content: &str) -> Result<Self> {
 72        if content.is_empty() {
 73            return Ok(Self::default());
 74        }
 75        parse_json_with_comments::<Self>(content)
 76    }
 77
 78    pub fn add_to_cx(self, cx: &mut AppContext) -> Result<()> {
 79        let key_equivalents = crate::key_equivalents::get_key_equivalents(&cx.keyboard_layout());
 80
 81        for KeymapBlock {
 82            context,
 83            use_key_equivalents,
 84            bindings,
 85        } in self.0
 86        {
 87            let bindings = bindings
 88                .into_iter()
 89                .filter_map(|(keystroke, action)| {
 90                    let action = action.0;
 91
 92                    // This is a workaround for a limitation in serde: serde-rs/json#497
 93                    // We want to deserialize the action data as a `RawValue` so that we can
 94                    // deserialize the action itself dynamically directly from the JSON
 95                    // string. But `RawValue` currently does not work inside of an untagged enum.
 96                    match action {
 97                        Value::Array(items) => {
 98                            let Ok([name, data]): Result<[serde_json::Value; 2], _> =
 99                                items.try_into()
100                            else {
101                                return Some(Err(anyhow!("Expected array of length 2")));
102                            };
103                            let serde_json::Value::String(name) = name else {
104                                return Some(Err(anyhow!(
105                                    "Expected first item in array to be a string."
106                                )));
107                            };
108                            cx.build_action(&name, Some(data))
109                        }
110                        Value::String(name) => cx.build_action(&name, None),
111                        Value::Null => Ok(no_action()),
112                        _ => {
113                            return Some(Err(anyhow!("Expected two-element array, got {action:?}")))
114                        }
115                    }
116                    .with_context(|| {
117                        format!(
118                            "invalid binding value for keystroke {keystroke}, context {context:?}"
119                        )
120                    })
121                    .log_err()
122                    .map(|action| {
123                        KeyBinding::load(
124                            &keystroke,
125                            action,
126                            context.as_deref(),
127                            if use_key_equivalents.unwrap_or_default() {
128                                key_equivalents.as_ref()
129                            } else {
130                                None
131                            },
132                        )
133                    })
134                })
135                .collect::<Result<Vec<_>>>()?;
136
137            cx.bind_keys(bindings);
138        }
139        Ok(())
140    }
141
142    pub fn generate_json_schema(
143        generator: SchemaGenerator,
144        action_schemas: Vec<(SharedString, Option<Schema>)>,
145        deprecations: &HashMap<SharedString, SharedString>,
146    ) -> serde_json::Value {
147        fn set<I, O>(input: I) -> Option<O>
148        where
149            I: Into<O>,
150        {
151            Some(input.into())
152        }
153
154        fn add_deprecation_notice(schema_object: &mut SchemaObject, new_name: &SharedString) {
155            schema_object.extensions.insert(
156                // deprecationMessage is not part of the JSON Schema spec,
157                // but json-language-server recognizes it.
158                "deprecationMessage".to_owned(),
159                format!("Deprecated, use {new_name}").into(),
160            );
161        }
162
163        let empty_object: SchemaObject = SchemaObject {
164            instance_type: set(InstanceType::Object),
165            ..Default::default()
166        };
167
168        let mut keymap_action_alternatives = Vec::new();
169        for (name, action_schema) in action_schemas.iter() {
170            let schema = if let Some(Schema::Object(schema)) = action_schema {
171                Some(schema.clone())
172            } else {
173                None
174            };
175
176            // If the type has a description, also apply it to the value. Ideally it would be
177            // removed and applied to the overall array, but `json-language-server` does not show
178            // these descriptions.
179            let description = schema.as_ref().and_then(|schema| {
180                schema
181                    .metadata
182                    .as_ref()
183                    .and_then(|metadata| metadata.description.as_ref())
184            });
185            let mut matches_action_name = SchemaObject {
186                const_value: Some(Value::String(name.to_string())),
187                ..Default::default()
188            };
189            if let Some(description) = description {
190                matches_action_name.metadata = set(Metadata {
191                    description: Some(description.clone()),
192                    ..Default::default()
193                });
194            }
195
196            // Add an alternative for plain action names.
197            let deprecation = deprecations.get(name);
198            let mut plain_action = SchemaObject {
199                instance_type: set(InstanceType::String),
200                const_value: Some(Value::String(name.to_string())),
201                ..Default::default()
202            };
203            if let Some(new_name) = deprecation {
204                add_deprecation_notice(&mut plain_action, new_name);
205            }
206            keymap_action_alternatives.push(plain_action.into());
207
208            // When all fields are skipped or an empty struct is added with impl_actions! /
209            // impl_actions_as! an empty struct is produced. The action should be invoked without
210            // data in this case.
211            if let Some(schema) = schema {
212                if schema != empty_object {
213                    let mut action_with_data = SchemaObject {
214                        instance_type: set(InstanceType::Array),
215                        array: Some(
216                            ArrayValidation {
217                                items: set(vec![matches_action_name.into(), schema.into()]),
218                                min_items: Some(2),
219                                max_items: Some(2),
220                                ..Default::default()
221                            }
222                            .into(),
223                        ),
224                        ..Default::default()
225                    };
226                    if let Some(new_name) = deprecation {
227                        add_deprecation_notice(&mut action_with_data, new_name);
228                    }
229                    keymap_action_alternatives.push(action_with_data.into());
230                }
231            }
232        }
233
234        // Placing null first causes json-language-server to default assuming actions should be
235        // null, so place it last.
236        keymap_action_alternatives.push(
237            SchemaObject {
238                instance_type: set(InstanceType::Null),
239                ..Default::default()
240            }
241            .into(),
242        );
243
244        let action_schema = SchemaObject {
245            subschemas: set(SubschemaValidation {
246                one_of: Some(keymap_action_alternatives),
247                ..Default::default()
248            }),
249            ..Default::default()
250        }
251        .into();
252
253        let mut root_schema = generator.into_root_schema_for::<KeymapFile>();
254        root_schema
255            .definitions
256            .insert("KeymapAction".to_owned(), action_schema);
257
258        serde_json::to_value(root_schema).unwrap()
259    }
260
261    pub fn blocks(&self) -> &[KeymapBlock] {
262        &self.0
263    }
264}
265
266fn no_action() -> Box<dyn gpui::Action> {
267    gpui::NoAction.boxed_clone()
268}
269
270#[cfg(test)]
271mod tests {
272    use crate::KeymapFile;
273
274    #[test]
275    fn can_deserialize_keymap_with_trailing_comma() {
276        let json = indoc::indoc! {"[
277              // Standard macOS bindings
278              {
279                \"bindings\": {
280                  \"up\": \"menu::SelectPrev\",
281                },
282              },
283            ]
284                  "
285
286        };
287        KeymapFile::parse(json).unwrap();
288    }
289}