func()

in matchtree.go [370:447]

• 68 lines of code
• 18 McCabe index (conditional complexity)

func (t *andLineMatchTree) matches(cp *contentProvider, cost int, known map[matchTree]bool) (bool, bool) {
	matches, sure := t.andMatchTree.matches(cp, cost, known)
	if !(sure && matches) {
		return matches, sure
	}

	// find child with fewest candidates
	min := maxUInt32
	fewestChildren := 0
	for ix, child := range t.children {
		v, ok := child.(*substrMatchTree)
		// make sure we are running a content search and that all candidates are a
		// substrMatchTree
		if !ok || v.fileName {
			return matches, sure
		}
		if len(v.current) < min {
			min = len(v.current)
			fewestChildren = ix
		}
	}

	type lineRange struct {
		start int
		end   int
	}
	lines := make([]lineRange, 0, len(t.children[fewestChildren].(*substrMatchTree).current))
	prev := -1
	for _, candidate := range t.children[fewestChildren].(*substrMatchTree).current {
		line, byteStart, byteEnd := candidate.line(cp.newlines(), cp.fileSize)
		if line == prev {
			continue
		}
		prev = line
		lines = append(lines, lineRange{byteStart, byteEnd})
	}

	// children keeps track of the children's candidates we have already seen.
	children := make([][]*candidateMatch, 0, len(t.children)-1)
	for j, child := range t.children {
		if j == fewestChildren {
			continue
		}
		children = append(children, child.(*substrMatchTree).current)
	}

nextLine:
	for i := 0; i < len(lines); i++ {
		hits := 1
	nextChild:
		for j := range children {
		nextCandidate:
			for len(children[j]) > 0 {
				candidate := children[j][0]
				bo := int(cp.findOffset(false, candidate.runeOffset))
				if bo < lines[i].start {
					children[j] = children[j][1:]
					continue nextCandidate
				}
				if bo <= lines[i].end {
					hits++
					continue nextChild
				}
				// move the `lines` iterator forward until bo <= line.end
				for i < len(lines) && bo > lines[i].end {
					i++
				}
				i--
				continue nextLine
			}
		}
		// return early once we found any line that contains matches from all children
		if hits == len(t.children) {
			return matches, true
		}
	}
	return false, true
}