33 lines
1.3 KiB
JavaScript
33 lines
1.3 KiB
JavaScript
// Holder counts, and the one rule that decides whether a count is "low".
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//
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// The block explorer's holders_count is optional: it is absent on a token it
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// has only just indexed, and it goes missing on a degraded or changed API.
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// Absent means the count is unknown. It does not mean the token has no
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// holders, and collapsing the two hides a token the user really holds as if
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// it were spam. Every call site reads the count through here so the
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// distinction cannot be lost again in one place while holding in the others.
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const LOW_HOLDER_THRESHOLD = 1000;
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// Parse an explorer-supplied holders_count into a number, or null when the
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// explorer did not report one. Anything unparseable is unknown too: a count
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// we cannot read is not a count of zero.
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function parseHoldersCount(raw) {
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if (raw === null || raw === undefined || raw === "") return null;
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const n = parseInt(raw, 10);
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return Number.isFinite(n) ? n : null;
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}
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// True only for a token the explorer reported as having fewer holders than
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// the threshold. An unknown count is never low: showing a spam token the
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// user can see is unusual costs less than hiding an asset they own.
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function isLowHolderCount(holders) {
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return holders != null && holders < LOW_HOLDER_THRESHOLD;
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}
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module.exports = {
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LOW_HOLDER_THRESHOLD,
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parseHoldersCount,
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isLowHolderCount,
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};
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