diff options
Diffstat (limited to 'deps/npm/node_modules/detect-indent/index.js')
-rw-r--r-- | deps/npm/node_modules/detect-indent/index.js | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/deps/npm/node_modules/detect-indent/index.js b/deps/npm/node_modules/detect-indent/index.js new file mode 100644 index 0000000000..eda0b1b1aa --- /dev/null +++ b/deps/npm/node_modules/detect-indent/index.js @@ -0,0 +1,122 @@ +'use strict'; + +// detect either spaces or tabs but not both to properly handle tabs +// for indentation and spaces for alignment +const INDENT_RE = /^(?:( )+|\t+)/; + +function getMostUsed(indents) { + let result = 0; + let maxUsed = 0; + let maxWeight = 0; + + for (const entry of indents) { + // TODO: use destructuring when targeting Node.js 6 + const key = entry[0]; + const val = entry[1]; + + const u = val[0]; + const w = val[1]; + + if (u > maxUsed || (u === maxUsed && w > maxWeight)) { + maxUsed = u; + maxWeight = w; + result = Number(key); + } + } + + return result; +} + +module.exports = str => { + if (typeof str !== 'string') { + throw new TypeError('Expected a string'); + } + + // used to see if tabs or spaces are the most used + let tabs = 0; + let spaces = 0; + + // remember the size of previous line's indentation + let prev = 0; + + // remember how many indents/unindents as occurred for a given size + // and how much lines follow a given indentation + // + // indents = { + // 3: [1, 0], + // 4: [1, 5], + // 5: [1, 0], + // 12: [1, 0], + // } + const indents = new Map(); + + // pointer to the array of last used indent + let current; + + // whether the last action was an indent (opposed to an unindent) + let isIndent; + + for (const line of str.split(/\n/g)) { + if (!line) { + // ignore empty lines + continue; + } + + let indent; + const matches = line.match(INDENT_RE); + + if (matches) { + indent = matches[0].length; + + if (matches[1]) { + spaces++; + } else { + tabs++; + } + } else { + indent = 0; + } + + const diff = indent - prev; + prev = indent; + + if (diff) { + // an indent or unindent has been detected + + isIndent = diff > 0; + + current = indents.get(isIndent ? diff : -diff); + + if (current) { + current[0]++; + } else { + current = [1, 0]; + indents.set(diff, current); + } + } else if (current) { + // if the last action was an indent, increment the weight + current[1] += Number(isIndent); + } + } + + const amount = getMostUsed(indents); + + let type; + let indent; + if (!amount) { + type = null; + indent = ''; + } else if (spaces >= tabs) { + type = 'space'; + indent = ' '.repeat(amount); + } else { + type = 'tab'; + indent = '\t'.repeat(amount); + } + + return { + amount, + type, + indent + }; +}; |