parse-makefile-rules.js

const ruleRegex = /^([^:\s]+):(?!=):?([^:\n]*)$/

module.exports = string => string.split('\n').concat('').reduce(({state, results}, line, index, lines) => (
      state.parsingRule?
            line.startsWith('\t')? {
                state: Object.assign(
                    {},
                    state,
                    {
                        ruleBody: state.ruleBody.concat(
                            line.trim()
                        )
                    }
                ),
                results
            }
          : /* otherwise        */ {
                state: {
                    parsingRule: false,
                    ruleBody: []
                },
                results: Object.assign(
                    {},
                    results,
                    {
                        [state.parsingRule]: state.ruleBody.join('\n')
                    }
                )
            }
    : line.match(ruleRegex)? {
          state: {
              parsingRule: RegExp.$1,
              ruleBody: []
          },
          results
      }
    : /* otherwise        */ {state, results, line}
), {state: {parsingRule: false, ruleBody: []}, results: {}}).results

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