How to check if a string contains text from an array of substrings in JavaScript?

Dealing with edge cases and scalability

Edge cases in your crosshairs

While the fast solution hits the bullseye for commonplace scenarios, below are edge cases to stay aware of:

1. Empty Strings: Be mindful of both your main string and substrings, ensuring none are empty. Empty substrings technically "exist" everywhere.
2. Empty Arrays: By default, no match should be found if the array of substrings is void of elements.
3. Regular Expression Special Characters: Substrings involving regex special characters warrant escaping when using regex for matching.

Keeping it efficient for big leagues

Prepping for large input scales, performance can be a hurdle. Steps for optimization considerations:

1. Narrow the search fields if substring locations in the main string are predictable.
2. Employ efficient data structures like trie or suffix arrays for complex applications.
3. Benchmark various methods to reach the optimal solution.

Exploring alternate pathways

There are alternate ways, besides some() and includes(), to hit your target:

// Pathway via indexOf
const hitTestIndex = ['apples', 'oranges'].some(sub => 'roving the oranges aisle'.indexOf(sub) !== -1);
// Route through regular expression
const pattern = new RegExp(['apples', 'oranges'].join('|'));
const hitTestRegex = pattern.test('roving the oranges aisle');
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The indexOf method works similarly to includes, but returns the first occurring index or -1. Regex, on the other hand, matches across numerous patterns simultaneously - this versatility enhances your arrows for various use cases.

Case sensitivity and special characters: Dealing with the nitty-gritty

Uniform case for fair play

In some cases, it's prudent to enforce case insensitive matching. Achieve this by:

const hitTestCaseInsensitive = ['apples', 'oranges'].some(sub =>
  'roving the ORANGES AISLE'.toLowerCase().includes(sub.toLowerCase())
);
// true - Case doesn't matter when you're hungry for oranges!
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Keeping special characters in check

Special characters in substrings require special attention too. Here's how to escape them when constructing a regex:

function tameRegex(string) {
  return string.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
}

const substrings = ['alpha(omega)', 'wall-e'];
const tameSubstrings = substrings.map(tameRegex);
const regexPattern = new RegExp(tameSubstrings.join('|'));
const hitSpecialCharTest = regexPattern.test('string with alpha(omega)');
// true - Even Greek Gods enjoy special treatment once in a while!
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Effective Implementations and Live Code

Identifying specific substrings

At times, knowing which substring was matched is crucial:

const substrings = ['apples', 'oranges'];
const mainStr = 'roving the oranges aisle';
const foundSub = substrings.find(sub => mainStr.includes(sub)) || "None found";
// "oranges" - Seems like we're making a fruit salad!
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Real-life code execution

A practical implementation helps to crystalize the concept. Here's a live code execution for that understanding:

// Let's put the theory to test
const substrings = ['react', 'vue', 'angular'];
const text = 'Building UI with react is fun';
const match = substrings.some(sub => text.includes(sub));

console.assert(match === true, 'React-ively seeking fun with UI building');
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Run the above snippet in your browser's console or any JSFiddle or CodePen test environment to visualise the execution.