Add simple headTail modifier (#2428)

- Fixes #2093

Only supports "head" applied to a single modifier. Eg doesn't support
"head inside curly". Let's see how annoying that is in practice

## Checklist

- [x] I have added
[tests](https://www.cursorless.org/docs/contributing/test-case-recorder/)
- [-] I have updated the
[docs](https://github.com/cursorless-dev/cursorless/tree/main/docs) and
[cheatsheet](https://github.com/cursorless-dev/cursorless/tree/main/cursorless-talon/src/cheatsheet)
- [-] I have not broken the cheatsheet

Author: pokey

packages/cursorless-vscode/src/keyboard/TokenTypes.ts

@@ -20,7 +20,13 @@ export interface SectionTypes {
   vscodeCommand: ModalVscodeCommandDescriptor;
   modifier: ModifierType;
 }
-type ModifierType = "nextPrev" | "every" | "interiorOnly" | "excludeInterior";
+type ModifierType =
+  | "nextPrev"
+  | "every"
+  | "interiorOnly"
+  | "excludeInterior"
+  | "extendThroughStartOf"
+  | "extendThroughEndOf";
 export type MiscValue =
   | "combineColorAndShape"
   | "makeRange"
@@ -65,6 +71,7 @@ export interface TokenTypeValueMap {
   // modifier config section
   nextPrev: "nextPrev";
   every: "every";
+  headTail: "extendThroughStartOf" | "extendThroughEndOf";
   simpleModifier: "interiorOnly" | "excludeInterior";
 
   digit: number;

packages/cursorless-vscode/src/keyboard/getTokenTypeKeyMaps.ts

@@ -68,6 +68,11 @@ export function getTokenTypeKeyMaps(
     // modifier config section
     every: config.getTokenKeyMap("every", "modifier", only("every")),
     nextPrev: config.getTokenKeyMap("nextPrev", "modifier", only("nextPrev")),
+    headTail: config.getTokenKeyMap(
+      "headTail",
+      "modifier",
+      only("extendThroughStartOf", "extendThroughEndOf"),
+    ),
     simpleModifier: config.getTokenKeyMap(
       "simpleModifier",
       "modifier",

packages/cursorless-vscode/src/keyboard/grammar/generated/grammar.ts

@@ -10,6 +10,7 @@ declare var wrap: any;
 declare var pairedDelimiter: any;
 declare var vscodeCommand: any;
 declare var simpleModifier: any;
+declare var headTail: any;
 declare var every: any;
 declare var nextPrev: any;
 declare var simpleScopeTypeType: any;
@@ -73,6 +74,9 @@ const grammar: Grammar = {
         },
     {"name": "main", "symbols": [(keyboardLexer.has("vscodeCommand") ? {type: "vscodeCommand"} : vscodeCommand)], "postprocess": command("vscodeCommand", ["command"])},
     {"name": "modifier", "symbols": [(keyboardLexer.has("simpleModifier") ? {type: "simpleModifier"} : simpleModifier)], "postprocess": capture({ type: $0 })},
+    {"name": "modifier", "symbols": [(keyboardLexer.has("headTail") ? {type: "headTail"} : headTail), "modifier"], "postprocess": 
+        ([type, modifier]) => ({ type, modifiers: [modifier] })
+        },
     {"name": "modifier", "symbols": ["scopeType"], "postprocess": capture({ type: "containingScope", scopeType: $0 })},
     {"name": "modifier", "symbols": [(keyboardLexer.has("every") ? {type: "every"} : every), "scopeType"], "postprocess": capture({ type: "everyScope", scopeType: $1 })},
     {"name": "modifier$ebnf$1", "symbols": ["offset"], "postprocess": id},

packages/cursorless-vscode/src/keyboard/grammar/grammar.ne

@@ -52,6 +52,12 @@ main -> %vscodeCommand {% command("vscodeCommand", ["command"]) %}
 # "inside", "bounds"
 modifier -> %simpleModifier {% capture({ type: $0 }) %}
 
+# "head" / "tail"
+# FIXME: Support "head inside curly" (ie multiple modifiers)
+modifier -> %headTail modifier {%
+  ([type, modifier]) => ({ type, modifiers: [modifier] })
+%}
+
 # "funk"
 modifier -> scopeType {% capture({ type: "containingScope", scopeType: $0 }) %}
 

packages/cursorless-vscode/src/keyboard/grammar/grammar.test.ts

@@ -139,6 +139,25 @@ const testCases: TestCase[] = [
       type: "modifyTarget",
     },
   },
+  {
+    tokens: [
+      { type: "headTail", value: "extendThroughStartOf" },
+      { type: "simpleModifier", value: "excludeInterior" },
+    ],
+    expected: {
+      arg: {
+        modifier: {
+          type: "extendThroughStartOf",
+          modifiers: [
+            {
+              type: "excludeInterior",
+            },
+          ],
+        },
+      },
+      type: "modifyTarget",
+    },
+  },
   {
     tokens: [
       {

packages/cursorless-vscode/src/keyboard/keyboard-config.fixture.json

@@ -69,7 +69,9 @@
     "n": "nextPrev",
     "*": "every",
     "mi": "interiorOnly",
-    "mb": "excludeInterior"
+    "mb": "excludeInterior",
+    "mh": "extendThroughStartOf",
+    "mt": "extendThroughEndOf"
   },
   "cursorless.experimental.keyboard.modal.keybindings.vscodeCommand": {
     "va": "editor.action.addCommentLine",