Data update

Task/Camel-case-and-snake-case/JavaScript/camel-case-and-snake-case.js

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+const HYPHEN = '-';
+const SPACE = ' ';
+const UNDERSCORE = '_';
+const WHITESPACE = " \n\r\t\f\v";
+
+function leftTrim(text) {
+  const start = text.search(/\S/); // Find the index of the first non-whitespace character
+  return start === -1 ? "" : text.substring(start);
+}
+
+function rightTrim(text) {
+  const end = text.search(/\S(?![\s\S]*\S)/); // Find the index of the last non-whitespace character
+  return end === -1 ? "" : text.substring(0, end + 1);
+}
+
+function trim(text) {
+  return leftTrim(rightTrim(text));
+}
+
+function prepareForConversion(text) {
+  text = trim(text);
+  text = text.replace(new RegExp(SPACE, 'g'), UNDERSCORE);
+  text = text.replace(new RegExp(HYPHEN, 'g'), UNDERSCORE);
+  return text; // Return the modified text
+}
+
+function toSnakeCase(camel) {
+  camel = prepareForConversion(camel);
+  let snake = "";
+  let first = true;
+  for (const ch of camel) {
+    if (first) {
+      snake += ch;
+      first = false;
+    } else if (!first && ch >= 'A' && ch <= 'Z') {
+      if (snake.slice(-1) === UNDERSCORE) {
+        snake += ch.toLowerCase();
+      } else {
+        snake += UNDERSCORE;
+        snake += ch.toLowerCase();
+      }
+    } else {
+      snake += ch;
+    }
+  }
+  return snake;
+}
+
+function toCamelCase(snake) {
+  snake = prepareForConversion(snake);
+  let camel = "";
+  let underscore = false;
+  for (const ch of snake) {
+    if (ch === UNDERSCORE) {
+      underscore = true;
+    } else if (underscore) {
+      camel += ch.toUpperCase();
+      underscore = false;
+    } else {
+      camel += ch;
+    }
+  }
+  return camel;
+}
+
+function main() {
+  const variableNames = ["snakeCase", "snake_case", "variable_10_case",
+    "variable10Case", "ergo rE tHis", "hurry-up-joe!", "c://my-docs/happy_Flag-Day/12.doc", "  spaces  "];
+
+  console.log("".padEnd(48, " ") + "=== To snake_case ===");
+  for (const text of variableNames) {
+    console.log("".padEnd(34, " ") + text + " --> " + toSnakeCase(text));
+  }
+
+  console.log("\n");
+  console.log("".padEnd(48, " ") + "=== To camelCase ===");
+  for (const text of variableNames) {
+    console.log("".padEnd(34, " ") + text + " --> " + toCamelCase(text));
+  }
+}
+
+main();