From 4f0a182734c482d46d4bcb7f2f8c8c823b3f9469 Mon Sep 17 00:00:00 2001
From: Kir_Antipov <kp.antipov@gmail.com>
Date: Mon, 30 Jan 2023 09:20:54 +0000
Subject: [PATCH] Made options for formatting TypeScript documents
---
.../typescript-formatting-options.ts | 192 ++++++++++++++++++
1 file changed, 192 insertions(+)
create mode 100644 src/utils/typescript/typescript-formatting-options.ts
diff --git a/src/utils/typescript/typescript-formatting-options.ts b/src/utils/typescript/typescript-formatting-options.ts
new file mode 100644
index 0000000..1fb31b6
--- /dev/null
+++ b/src/utils/typescript/typescript-formatting-options.ts
@@ -0,0 +1,192 @@
+import { DEFAULT_NEWLINE } from "@/utils/environment";
+
+/**
+ * Represents options for formatting TypeScript code as a string.
+ */
+export interface TypeScriptFormattingOptions {
+ /**
+ * The character(s) to use for a single indentation level.
+ *
+ * If not specified, the value of {@link DEFAULT_TAB} (4 spaces) will be used.
+ */
+ tab?: string;
+
+ /**
+ * The number of spaces to use for a single indentation level.
+ *
+ * If not specified, the value of {@link DEFAULT_TAB_SIZE} (`4`) will be used.
+ */
+ tabSize?: number;
+
+ /**
+ * The number of indentation levels to apply.
+ *
+ * If not specified, no indentation will be applied.
+ */
+ indent?: number;
+
+ /**
+ * The characters to use for line breaks.
+ *
+ * If not specified, the value of {@link DEFAULT_NEWLINE} (`\r\n` on Windows, `\n` on Unix) will be used.
+ */
+ newline?: string;
+
+ /**
+ * The preferred style for quoting strings in the formatted code.
+ *
+ * If not specified, the value of {@link DEFAULT_QUOTES} (double quotes, `"`) will be used.
+ */
+ preferredQuotes?: string;
+}
+
+/**
+ * The default string to use for a single indentation level.
+ */
+export const DEFAULT_TAB = " ";
+
+/**
+ * The default number of spaces to use for a single indentation level.
+ */
+export const DEFAULT_TAB_SIZE = 4;
+
+/**
+ * The default style for quoting strings in the formatted code.
+ */
+export const DEFAULT_QUOTES = "\"";
+
+export { DEFAULT_NEWLINE, UNIX_NEWLINE, WINDOWS_NEWLINE } from "@/utils/environment";
+
+/**
+ * Returns the string to use for a single indentation level, based on the given formatting options.
+ *
+ * @param options - The formatting options to use. If not provided, default values will be used.
+ *
+ * @returns The string to use for a single indentation level.
+ */
+export function getTab(options?: TypeScriptFormattingOptions): string {
+ // If a specific tab character is specified, use it.
+ if (typeof options?.tab === "string") {
+ return options.tab;
+ }
+
+ // If a specific tab size is specified and it's not the same as the default, generate a new tab string from it.
+ if (typeof options?.tabSize === "number" && options.tabSize !== DEFAULT_TAB_SIZE) {
+ return createTab(options.tabSize);
+ }
+
+ // Otherwise, use the default tab string.
+ return DEFAULT_TAB;
+}
+
+/**
+ * Returns the indentation string to use based on the given formatting options.
+ *
+ * @param options - The formatting options to use. If not provided, default values will be used.
+ *
+ * @returns The indentation string to use.
+ */
+export function getIndentation(options?: TypeScriptFormattingOptions): string {
+ const tab = getTab(options);
+ return createIndentation(tab, options?.indent || 0);
+}
+
+/**
+ * Returns the string to use for line breaks based on the given formatting options.
+ *
+ * @param options - The formatting options to use. If not provided, default values will be used.
+ * @returns The string to use for line breaks.
+ */
+export function getNewline(options?: TypeScriptFormattingOptions): string {
+ // If a specific newline character sequence is specified, use it.
+ // Otherwise, use the default line break character sequence based on the current operating system.
+ return typeof options?.newline === "string" ? options.newline : DEFAULT_NEWLINE;
+}
+
+/**
+ * Returns the preferred style for quoting strings based on the given formatting options.
+ *
+ * @param options - The formatting options to use. If not provided, default values will be used.
+ *
+ * @returns The preferred style for quoting strings.
+ */
+export function getQuotes(options?: TypeScriptFormattingOptions): string {
+ // If a specific quote style is specified, use it.
+ // Otherwise, use the default quote string.
+ return typeof options?.preferredQuotes === "string" ? options.preferredQuotes : DEFAULT_QUOTES;
+}
+
+/**
+ * Returns a new set of formatting options with the indentation level incremented by the given amount.
+ *
+ * @param options - The formatting options to use as the starting point. If not provided, default values will be used.
+ * @param step - The number of indentation levels to add. Defaults to `1` if not provided.
+ *
+ * @returns A new set of formatting options with the incremented indentation level.
+ */
+export function incrementIndent(options?: TypeScriptFormattingOptions, step?: number): TypeScriptFormattingOptions {
+ const indent = (options?.indent || 0) + (step ?? 1);
+ return { ...options, indent };
+}
+
+/**
+ * A cache of previously generated tab strings, keyed by their length.
+ */
+const CACHED_TABS = new Map<number, string>([
+ [DEFAULT_TAB_SIZE, DEFAULT_TAB],
+]);
+
+/**
+ * Generates a string of spaces with the given width to use as an indentation level.
+ *
+ * @param tabSize - The number of spaces for a single indentation level.
+ *
+ * @returns The generated tab string.
+ */
+function createTab(tabSize: number): string {
+ const cachedTab = CACHED_TABS.get(tabSize);
+ if (cachedTab !== undefined) {
+ return cachedTab;
+ }
+
+ const generatedTab = " ".repeat(tabSize);
+ CACHED_TABS.set(tabSize, generatedTab);
+ return generatedTab;
+}
+
+/**
+ * A cache of previously generated indentation strings, keyed by the combination of their `tab` and `indent` values.
+ */
+const CACHED_INDENTATION = new Map<string, Map<number, string>>();
+
+/**
+ * Generates a string of spaces using the provided tab string and indent count.
+ *
+ * @param tab - The string to use for a single indentation level.
+ * @param indent - The number of indentation levels to apply.
+ *
+ * @returns The generated indentation string.
+ */
+function createIndentation(tab: string, indent: number): string {
+ if (!indent) {
+ return "";
+ }
+
+ if (indent === 1) {
+ return tab;
+ }
+
+ const cachedIndentationsByTab = CACHED_INDENTATION.get(tab) || new Map<number, string>();
+ if (!cachedIndentationsByTab.size) {
+ CACHED_INDENTATION.set(tab, cachedIndentationsByTab);
+ }
+
+ const cachedIndentation = cachedIndentationsByTab.get(indent);
+ if (cachedIndentation !== undefined) {
+ return cachedIndentation;
+ }
+
+ const generatedIndentation = tab.repeat(indent);
+ cachedIndentationsByTab.set(indent, generatedIndentation);
+ return generatedIndentation;
+}