refactor(ini): simplify parse()

ini/_ini_map.ts

@@ -49,21 +49,10 @@ export type ReviverFunction = (
   section?: string,
 ) => unknown;
 
-const ASSIGNMENT_MARK = "=";
-
 function isPlainObject(object: unknown): object is object {
   return Object.prototype.toString.call(object) === "[object Object]";
 }
 
-function trimQuotes(value: string): string {
-  if (value.startsWith('"') && value.endsWith('"')) {
-    return value.slice(1, -1);
-  }
-  return value;
-}
-
-const NON_WHITESPACE_REGEXP = /\S/;
-
 /**
  * Class implementation for fine control of INI data structures.
  */
@@ -206,32 +195,6 @@ export class IniMap {
     }
   }
 
-  *#readTextLines(text: string): Generator<string> {
-    const { length } = text;
-    let line = "";
-
-    for (let i = 0; i < length; i += 1) {
-      const char = text[i]!;
-
-      if (char === "\n" || char === "\r") {
-        yield line;
-        line = "";
-        if (char === "\r" && text[i + 1] === "\n") {
-          i++;
-          if (!this.#formatting.lineBreak) {
-            this.#formatting.lineBreak = "\r\n";
-          }
-        } else if (!this.#formatting.lineBreak) {
-          this.#formatting.lineBreak = char;
-        }
-      } else {
-        line += char;
-      }
-    }
-
-    yield line;
-  }
-
   /**
    * Convert this `IniMap` to a plain object.
    *
@@ -269,108 +232,6 @@ export class IniMap {
     return obj;
   }
 
-  /**
-   * Parse an INI string in this `IniMap`.
-   *
-   * @param text The text to parse
-   * @param reviver The reviver function
-   * @returns This {@code IniMap} object
-   */
-  parse(text: string, reviver?: ReviverFunction): this {
-    if (typeof text !== "string") {
-      throw new SyntaxError(`Unexpected token ${text} in INI at line 0`);
-    }
-
-    reviver ??= (_key, value, _section) => {
-      if (!isNaN(+value) && !value.includes('"')) return +value;
-      if (value === "null") return null;
-      if (value === "true" || value === "false") return value === "true";
-      return trimQuotes(value);
-    };
-
-    let lineNumber = 1;
-    let currentSection: LineSection | undefined;
-
-    for (const line of this.#readTextLines(text)) {
-      const trimmed = line.trim();
-      if (isComment(trimmed)) {
-        this.#lines.push({
-          type: "comment",
-          num: lineNumber,
-          val: trimmed,
-        });
-      } else if (isSection(trimmed, lineNumber)) {
-        const sec = trimmed.substring(1, trimmed.length - 1);
-
-        if (!NON_WHITESPACE_REGEXP.test(sec)) {
-          throw new SyntaxError(
-            `Unexpected empty section name at line ${lineNumber}`,
-          );
-        }
-
-        currentSection = {
-          type: "section",
-          num: lineNumber,
-          sec,
-          map: new Map<string, LineValue>(),
-          end: lineNumber,
-        };
-        this.#lines.push(currentSection);
-        this.#sections.set(currentSection.sec, currentSection);
-      } else {
-        const assignmentPos = trimmed.indexOf(ASSIGNMENT_MARK);
-
-        if (assignmentPos === -1) {
-          throw new SyntaxError(
-            `Unexpected token ${trimmed[0]} in INI at line ${lineNumber}`,
-          );
-        }
-        if (assignmentPos === 0) {
-          throw new SyntaxError(
-            `Unexpected empty key name at line ${lineNumber}`,
-          );
-        }
-
-        const leftHand = trimmed.substring(0, assignmentPos);
-        const rightHand = trimmed.substring(assignmentPos + 1);
-
-        if (this.#formatting.pretty === undefined) {
-          this.#formatting.pretty = leftHand.endsWith(" ") &&
-            rightHand.startsWith(" ");
-        }
-
-        const key = leftHand.trim();
-        const value = rightHand.trim();
-
-        if (currentSection) {
-          const lineValue: LineValue = {
-            type: "value",
-            num: lineNumber,
-            sec: currentSection.sec,
-            key,
-            val: reviver(key, value, currentSection.sec),
-          };
-          currentSection.map.set(key, lineValue);
-          this.#lines.push(lineValue);
-          currentSection.end = lineNumber;
-        } else {
-          const lineValue: LineValue = {
-            type: "value",
-            num: lineNumber,
-            key,
-            val: reviver(key, value),
-          };
-          this.#global.set(key, lineValue);
-          this.#lines.push(lineValue);
-        }
-      }
-
-      lineNumber += 1;
-    }
-
-    return this;
-  }
-
   /**
    * Create an `IniMap` from an INI string.
    *
@@ -414,34 +275,11 @@ export class IniMap {
           ini.set(key, val);
         }
       }
-    } else {
-      ini.parse(input, formatting?.reviver);
     }
     return ini;
   }
 }
 
-/** Detect supported comment styles. */
-function isComment(input: string): boolean {
-  return input === "" ||
-    input.startsWith("#") ||
-    input.startsWith(";") ||
-    input.startsWith("//");
-}
-
-/** Detect a section start. */
-function isSection(input: string, lineNumber: number): boolean {
-  if (input.startsWith("[")) {
-    if (input.endsWith("]")) {
-      return true;
-    }
-    throw new SyntaxError(
-      `Unexpected end of INI section at line ${lineNumber}`,
-    );
-  }
-  return false;
-}
-
 type LineOp = typeof LineOp[keyof typeof LineOp];
 const LineOp = {
   Del: -1,

ini/parse.ts

@@ -1,9 +1,63 @@
 // Copyright 2018-2025 the Deno authors. MIT license.
 // This module is browser compatible.
 
-import { IniMap, type ReviverFunction } from "./_ini_map.ts";
+import type { ReviverFunction } from "./_ini_map.ts";
 export type { ReviverFunction };
 
+const SECTION_REGEXP = /^\[(?<name>.*\S.*)]$/;
+const KEY_VALUE_REGEXP = /^(?<key>.*?)\s*=\s*(?<value>.*?)$/;
+
+function trimQuotes(value: string): string {
+  if (value.startsWith('"') && value.endsWith('"')) {
+    return value.slice(1, -1);
+  }
+  return value;
+}
+
+/** Detect supported comment styles. */
+function isComment(input: string): boolean {
+  return (
+    input.startsWith("#") ||
+    input.startsWith(";") ||
+    input.startsWith("//")
+  );
+}
+
+/** Detect a section start. */
+function isSection(input: string, lineNumber: number): boolean {
+  if (input.startsWith("[")) {
+    if (input.endsWith("]")) {
+      return true;
+    }
+    throw new SyntaxError(
+      `Unexpected end of INI section at line ${lineNumber}`,
+    );
+  }
+  return false;
+}
+
+function* readTextLines(text: string): Generator<string> {
+  let line = "";
+  for (let i = 0; i < text.length; i += 1) {
+    const char = text[i];
+    switch (char) {
+      case "\n":
+        yield line;
+        line = "";
+        break;
+      case "\r":
+        yield line;
+        line = "";
+        if (text[i + 1] === "\n") i += 1;
+        break;
+      default:
+        line += char;
+        break;
+    }
+  }
+  yield line;
+}
+
 /** Options for {@linkcode parse}. */
 export interface ParseOptions {
   /**
@@ -14,6 +68,13 @@ export interface ParseOptions {
   reviver?: ReviverFunction;
 }
 
+function defaultReviver(_key: string, value: string, _section?: string) {
+  if (!isNaN(+value) && !value.includes('"')) return +value;
+  if (value === "null") return null;
+  if (value === "true" || value === "false") return value === "true";
+  return trimQuotes(value);
+}
+
 /**
  * Parse an INI config string into an object.
  *
@@ -81,7 +142,69 @@ export interface ParseOptions {
  */
 export function parse<T extends object>(
   text: string,
-  options?: ParseOptions,
+  options: ParseOptions = {},
 ): T {
-  return IniMap.from(text, options).toObject<T>();
+  if (typeof text !== "string") {
+    throw new SyntaxError(`Unexpected token ${text} in INI at line 0`);
+  }
+
+  const { reviver = defaultReviver } = options;
+
+  const root = {} as T;
+  let object: object = root;
+  let sectionName: string | undefined;
+
+  let lineNumber = 0;
+  for (let line of readTextLines(text)) {
+    line = line.trim();
+    lineNumber += 1;
+
+    // skip empty lines
+    if (line === "") continue;
+
+    // skip comment
+    if (isComment(line)) continue;
+
+    if (isSection(line, lineNumber)) {
+      sectionName = SECTION_REGEXP.exec(line)?.groups?.name;
+      if (!sectionName) {
+        throw new SyntaxError(
+          `Unexpected empty section name at line ${lineNumber}`,
+        );
+      }
+
+      object = {};
+      Object.defineProperty(root, sectionName, {
+        value: object,
+        writable: true,
+        enumerable: true,
+        configurable: true,
+      });
+
+      continue;
+    }
+
+    const groups = KEY_VALUE_REGEXP.exec(line)?.groups;
+
+    if (!groups) {
+      throw new SyntaxError(
+        `Unexpected token ${line[0]} in INI at line ${lineNumber}`,
+      );
+    }
+
+    const { key, value } = groups as { key: string; value: string };
+    if (!key.length) {
+      throw new SyntaxError(`Unexpected empty key name at line ${lineNumber}`);
+    }
+
+    const val = reviver(key, value, sectionName);
+    Object.defineProperty(object, key, {
+      value: val,
+      writable: true,
+      enumerable: true,
+      configurable: true,
+    });
+  }
+
+  return root;
 }

ini/parse_test.ts

@@ -84,6 +84,11 @@ Deno.test({
       SyntaxError,
       "Unexpected empty section name at line 1",
     );
+    assertInvalidParse(
+      "[ ]\na=1",
+      SyntaxError,
+      "Unexpected empty section name at line 1",
+    );
     assertInvalidParse(
       `=100`,
       SyntaxError,
@@ -230,3 +235,34 @@ Deno.test({
     assertEquals(parse("value=true\t"), { value: true });
   },
 });
+
+Deno.test({
+  name: "parse() parses padded lines",
+  fn() {
+    assertEquals(parse("  value=true"), { value: true });
+    assertEquals(parse("\tvalue=true"), { value: true });
+    assertEquals(parse("value  =true"), { value: true });
+    assertEquals(parse("value\t=true"), { value: true });
+    assertEquals(parse("value=  true"), { value: true });
+    assertEquals(parse("value=\ttrue"), { value: true });
+    assertEquals(parse("value=  true  "), { value: true });
+    assertEquals(parse("value=true\t"), { value: true });
+    assertEquals(parse("  \tvalue  \t=  \ttrue  \t"), { value: true });
+    assertEquals(parse("[s]"), { s: {} });
+    assertEquals(parse("[ s ]"), { " s ": {} });
+    assertEquals(parse("[section]"), { section: {} });
+    assertEquals(parse("[ section ]"), { " section ": {} });
+
+    assertEquals(parse("  [section]"), { section: {} });
+    assertEquals(parse("\t[section]"), { section: {} });
+    assertEquals(parse("[section]  "), { section: {} });
+    assertEquals(parse("[section]\t"), { section: {} });
+    assertEquals(parse("  \t[section]  \t"), { section: {} });
+
+    assertEquals(parse(" value=true "), { value: true });
+    assertEquals(parse('  value = "abc"  '), { value: "abc" });
+    assertEquals(parse("  [section]  \n  value  =  foo  "), {
+      section: { value: "foo" },
+    });
+  },
+});