Horz/Vert distance constraint with modal workflow (#43)

* button style tweak

* Remove duplication constraint ast transforms

* giveSketchFnCallTag to return if line already had a tag

* remove duplication

* update tag name to referenceSegName

* Update transform shape to return key details about the transform

* add modal to hor vert distance workflow

* fix browser env stuff from breaking tests

* fmt

src/lang/modifyAst.ts

@@ -481,15 +481,17 @@ export function createBinaryExpression([left, operator, right]: [
 
 export function giveSketchFnCallTag(
   ast: Program,
-  range: Range
-): { modifiedAst: Program; tag: string } {
+  range: Range,
+  tag?: string
+): { modifiedAst: Program; tag: string; isTagExisting: boolean } {
   const { node: primaryCallExp } = getNodeFromPath<CallExpression>(
     ast,
     getNodePathFromSourceRange(ast, range)
   )
   const firstArg = getFirstArg(primaryCallExp)
+  const isTagExisting = !!firstArg.tag
   const tagValue = (firstArg.tag ||
-    createLiteral(findUniqueName(ast, 'seg', 2))) as Literal
+    createLiteral(tag || findUniqueName(ast, 'seg', 2))) as Literal
   const tagStr = String(tagValue.value)
   const newFirstArg = createFirstArg(
     primaryCallExp.callee.name as TooTip,
@@ -500,5 +502,6 @@ export function giveSketchFnCallTag(
   return {
     modifiedAst: ast,
     tag: tagStr,
+    isTagExisting,
   }
 }