Add formatting rule for import type import keyword and open paren (microsoft#23872)

Author: weswigham

src/services/formatting/rules.ts

@@ -59,6 +59,8 @@ namespace ts.formatting {
             rule("NoSpaceBeforeDot", anyToken, SyntaxKind.DotToken, [isNonJsxSameLineTokenContext], RuleAction.Delete),
             rule("NoSpaceAfterDot", SyntaxKind.DotToken, anyToken, [isNonJsxSameLineTokenContext], RuleAction.Delete),
 
+            rule("NoSpaceBetweenImportParenInImportType", SyntaxKind.ImportKeyword, SyntaxKind.OpenParenToken, [isNonJsxSameLineTokenContext, isImportTypeContext], RuleAction.Delete),
+
             // Special handling of unary operators.
             // Prefix operators generally shouldn't have a space between
             // them and their target unary expression.
@@ -641,6 +643,10 @@ namespace ts.formatting {
         return context.contextNode.kind === SyntaxKind.ArrowFunction;
     }
 
+    function isImportTypeContext(context: FormattingContext): boolean {
+        return context.contextNode.kind === SyntaxKind.ImportType;
+    }
+
     function isNonJsxSameLineTokenContext(context: FormattingContext): boolean {
         return context.TokensAreOnSameLine() && context.contextNode.kind !== SyntaxKind.JsxText;
     }

tests/cases/fourslash/importTypeFormatting.ts

@@ -0,0 +1,9 @@
+/// <reference path="fourslash.ts"/>
+
+////var y: import("./c2").mytype;
+////var z: import ("./c2").mytype;
+
+format.document();
+verify.currentFileContentIs(
+`var y: import("./c2").mytype;
+var z: import("./c2").mytype;`);