add Go branch scope support (#1854)

Not all the behavior is perfect (I'm looking at you, pour and drink),
but it's better than not existing.

The perfect is the enemy of the good.

## 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

---------

Co-authored-by: pre-commit-ci-lite[bot] <117423508+pre-commit-ci-lite[bot]@users.noreply.github.com>
Co-authored-by: Pokey Rule <[email protected]>

data/playground/go/branch.go

@@ -0,0 +1,57 @@
+package p
+
+func switches(x any) {
+	switch x {
+	case 1:
+		// bar
+	case 2:
+		x = nil
+	case "s":
+	case 4, "t":
+		x = 7
+	// qux
+	case 5:
+		// foo
+		fallthrough
+	default:
+		panic("x")
+	}
+	switch x := x.(type) {
+	case int:
+		x++
+	case string, struct{}:
+		println(x)
+	default:
+		panic(x)
+	}
+	switch {
+	case x == 1:
+		panic("one")
+	case false:
+		// unreachable
+	}
+}
+
+func ifElseChains(x int) {
+	if y := 0; x == 1 {
+		// foo
+	} else if z:=0; x == 2 {
+		x--
+		x--
+		x--
+	} else if z:=0; x == 2 {
+		x--
+		x--
+		x--
+	} else if x == 3 {
+		x++
+	} else if x == 3 {
+		x++
+	} else {
+		x *= 2
+	}
+
+	if x == 4{
+		x++
+	}
+}

packages/common/src/types/Position.ts

@@ -1,4 +1,4 @@
-import { Range } from "..";
+import { Range, TextDocument } from "..";
 
 export class Position {
   /**
@@ -151,3 +151,19 @@ export class Position {
     return this.concise();
   }
 }
+
+/**
+ * adjustPosition returns a new position that is offset by the given amount.
+ * It corrects line and character positions to remain valid in doc.
+ * @param doc The document
+ * @param pos The position to adjust
+ * @param by The amount to adjust by
+ * @returns The adjusted position
+ */
+export function adjustPosition(
+  doc: TextDocument,
+  pos: Position,
+  by: number,
+): Position {
+  return doc.positionAt(doc.offsetAt(pos) + by);
+}

packages/cursorless-engine/src/languages/TreeSitterQuery/queryPredicateOperators.ts

@@ -1,4 +1,4 @@
-import { Range } from "@cursorless/common";
+import { Range, adjustPosition } from "@cursorless/common";
 import { z } from "zod";
 import { makeRangeFromPositions } from "../../util/nodeSelectors";
 import { MutableQueryCapture } from "./QueryCapture";
@@ -139,6 +139,26 @@ class ShrinkToMatch extends QueryPredicateOperator<ShrinkToMatch> {
   }
 }
 
+/**
+ * A predicate operator that modifies the range of the match by trimming trailing whitespace,
+ * similar to the javascript trimEnd function.
+ */
+class TrimEnd extends QueryPredicateOperator<TrimEnd> {
+  name = "trim-end!" as const;
+  schema = z.tuple([q.node]);
+
+  run(nodeInfo: MutableQueryCapture) {
+    const { document, range } = nodeInfo;
+    const text = document.getText(range);
+    const whitespaceLength = text.length - text.trimEnd().length;
+    nodeInfo.range = new Range(
+      range.start,
+      adjustPosition(document, range.end, -whitespaceLength),
+    );
+    return true;
+  }
+}
+
 /**
  * Indicates that it is ok for multiple captures to have the same domain but
  * different targets.  For example, if we have the query `(#allow-multiple!
@@ -197,6 +217,7 @@ class InsertionDelimiter extends QueryPredicateOperator<InsertionDelimiter> {
 export const queryPredicateOperators = [
   new Log(),
   new NotType(),
+  new TrimEnd(),
   new NotParentType(),
   new IsNthChild(),
   new ChildRange(),

packages/cursorless-vscode-e2e/src/suite/fixtures/recorded/languages/go/changeBranch.yml

@@ -0,0 +1,23 @@
+languageId: go
+command:
+  version: 6
+  spokenForm: change branch
+  action:
+    name: clearAndSetSelection
+    target:
+      type: primitive
+      modifiers:
+        - type: containingScope
+          scopeType: {type: branch}
+  usePrePhraseSnapshot: true
+initialState:
+  documentContents: "if x {\n\tx++\n} else {\n\tx--\n}"
+  selections:
+    - anchor: {line: 4, character: 1}
+      active: {line: 4, character: 1}
+  marks: {}
+finalState:
+  documentContents: "if x {\n\tx++\n} "
+  selections:
+    - anchor: {line: 2, character: 2}
+      active: {line: 2, character: 2}

packages/cursorless-vscode-e2e/src/suite/fixtures/recorded/languages/go/changeBranch2.yml

@@ -0,0 +1,23 @@
+languageId: go
+command:
+  version: 6
+  spokenForm: change branch
+  action:
+    name: clearAndSetSelection
+    target:
+      type: primitive
+      modifiers:
+        - type: containingScope
+          scopeType: {type: branch}
+  usePrePhraseSnapshot: true
+initialState:
+  documentContents: "if x {\n\tx++\n} else {\n\tx--\n}"
+  selections:
+    - anchor: {line: 0, character: 0}
+      active: {line: 0, character: 0}
+  marks: {}
+finalState:
+  documentContents: " else {\n\tx--\n}"
+  selections:
+    - anchor: {line: 0, character: 0}
+      active: {line: 0, character: 0}

packages/cursorless-vscode-e2e/src/suite/fixtures/recorded/languages/go/changeBranch3.yml

@@ -0,0 +1,23 @@
+languageId: go
+command:
+  version: 6
+  spokenForm: change branch
+  action:
+    name: clearAndSetSelection
+    target:
+      type: primitive
+      modifiers:
+        - type: containingScope
+          scopeType: {type: branch}
+  usePrePhraseSnapshot: true
+initialState:
+  documentContents: "if x {\n\tx++\n} else if y {\n\ty++\n} else {\n\tx--\n}"
+  selections:
+    - anchor: {line: 2, character: 7}
+      active: {line: 2, character: 7}
+  marks: {}
+finalState:
+  documentContents: "if x {\n\tx++\n}  else {\n\tx--\n}"
+  selections:
+    - anchor: {line: 2, character: 2}
+      active: {line: 2, character: 2}

packages/cursorless-vscode-e2e/src/suite/fixtures/recorded/languages/go/changeBranchAir.yml

@@ -0,0 +1,36 @@
+languageId: go
+command:
+  version: 6
+  spokenForm: change branch air
+  action:
+    name: clearAndSetSelection
+    target:
+      type: primitive
+      mark: {type: decoratedSymbol, symbolColor: default, character: a}
+      modifiers:
+        - type: containingScope
+          scopeType: {type: branch}
+  usePrePhraseSnapshot: true
+initialState:
+  documentContents: |-
+    switch x {
+    case 1:
+    case 2:
+        panic(x)
+    }
+  selections:
+    - anchor: {line: 4, character: 1}
+      active: {line: 4, character: 1}
+  marks:
+    default.a:
+      start: {line: 2, character: 0}
+      end: {line: 2, character: 4}
+finalState:
+  documentContents: |-
+    switch x {
+    case 1:
+
+    }
+  selections:
+    - anchor: {line: 2, character: 0}
+      active: {line: 2, character: 0}

packages/cursorless-vscode-e2e/src/suite/fixtures/recorded/languages/go/changeBranchCap.yml

@@ -0,0 +1,35 @@
+languageId: go
+command:
+  version: 6
+  spokenForm: change branch cap
+  action:
+    name: clearAndSetSelection
+    target:
+      type: primitive
+      mark: {type: decoratedSymbol, symbolColor: default, character: c}
+      modifiers:
+        - type: containingScope
+          scopeType: {type: branch}
+  usePrePhraseSnapshot: true
+initialState:
+  documentContents: |-
+    switch x {
+    case 1:
+    case 2:
+    }
+  selections:
+    - anchor: {line: 2, character: 7}
+      active: {line: 2, character: 7}
+  marks:
+    default.c:
+      start: {line: 1, character: 0}
+      end: {line: 1, character: 4}
+finalState:
+  documentContents: |-
+    switch x {
+
+    case 2:
+    }
+  selections:
+    - anchor: {line: 1, character: 0}
+      active: {line: 1, character: 0}

packages/cursorless-vscode-e2e/src/suite/fixtures/recorded/languages/go/changeBranchCap2.yml

@@ -0,0 +1,37 @@
+languageId: go
+command:
+  version: 6
+  spokenForm: change branch cap
+  action:
+    name: clearAndSetSelection
+    target:
+      type: primitive
+      mark: {type: decoratedSymbol, symbolColor: default, character: c}
+      modifiers:
+        - type: containingScope
+          scopeType: {type: branch}
+  usePrePhraseSnapshot: true
+initialState:
+  documentContents: |-
+    switch x := x.(type) {
+    case int:
+    default:
+        panic(x)
+    }
+  selections:
+    - anchor: {line: 2, character: 8}
+      active: {line: 2, character: 8}
+  marks:
+    default.c:
+      start: {line: 1, character: 0}
+      end: {line: 1, character: 4}
+finalState:
+  documentContents: |-
+    switch x := x.(type) {
+
+    default:
+        panic(x)
+    }
+  selections:
+    - anchor: {line: 1, character: 0}
+      active: {line: 1, character: 0}

packages/cursorless-vscode-e2e/src/suite/fixtures/recorded/languages/go/changeBranchDrum.yml

@@ -0,0 +1,36 @@
+languageId: go
+command:
+  version: 6
+  spokenForm: change branch drum
+  action:
+    name: clearAndSetSelection
+    target:
+      type: primitive
+      mark: {type: decoratedSymbol, symbolColor: default, character: d}
+      modifiers:
+        - type: containingScope
+          scopeType: {type: branch}
+  usePrePhraseSnapshot: true
+initialState:
+  documentContents: |-
+    switch x := x.(type) {
+    case int:
+    default:
+        panic(x)
+    }
+  selections:
+    - anchor: {line: 2, character: 8}
+      active: {line: 2, character: 8}
+  marks:
+    default.d:
+      start: {line: 2, character: 0}
+      end: {line: 2, character: 7}
+finalState:
+  documentContents: |-
+    switch x := x.(type) {
+    case int:
+
+    }
+  selections:
+    - anchor: {line: 2, character: 0}
+      active: {line: 2, character: 0}

packages/cursorless-vscode-e2e/src/suite/fixtures/recorded/languages/go/changeEveryBranch.yml

@@ -0,0 +1,27 @@
+languageId: go
+command:
+  version: 6
+  spokenForm: change every branch
+  action:
+    name: clearAndSetSelection
+    target:
+      type: primitive
+      modifiers:
+        - type: everyScope
+          scopeType: {type: branch}
+  usePrePhraseSnapshot: true
+initialState:
+  documentContents: "if x {\n\tx++\n} else if y {\n\ty++\n} else {\n\tx--\n}"
+  selections:
+    - anchor: {line: 0, character: 1}
+      active: {line: 0, character: 1}
+  marks: {}
+finalState:
+  documentContents: "  "
+  selections:
+    - anchor: {line: 0, character: 0}
+      active: {line: 0, character: 0}
+    - anchor: {line: 0, character: 1}
+      active: {line: 0, character: 1}
+    - anchor: {line: 0, character: 2}
+      active: {line: 0, character: 2}