func parseScript()

in internal/webtest/webtest.go [478:652]

• 153 lines of code
• 42 McCabe index (conditional complexity)

func parseScript(file, text string) (*script, error) {
	var current struct {
		Case      *case_
		Multiline *string
	}
	script := new(script)
	lastLineWasBlank := true
	lineno := 0
	line := ""
	errorf := func(format string, args ...interface{}) error {
		if line != "" {
			line = "\n" + line
		}
		return fmt.Errorf("%s:%d: %v%s", file, lineno, fmt.Sprintf(format, args...), line)
	}
	for text != "" {
		lineno++
		prevLine := line
		line, text, _ = cut(text, "\n")
		if strings.HasPrefix(line, "#") {
			continue
		}
		line = strings.TrimRight(line, " \t")
		if line == "" {
			lastLineWasBlank = true
			continue
		}
		what, args := splitOneField(line)

		// Add indented line to current multiline check, or else it ends.
		if what == "" {
			// Line is indented.
			if current.Multiline != nil {
				lastLineWasBlank = false
				*current.Multiline += args + "\n"
				continue
			}
			return nil, errorf("unexpected indented line")
		}

		// Multiline text is over; must be present.
		if current.Multiline != nil && *current.Multiline == "" {
			lineno--
			line = prevLine
			return nil, errorf("missing multiline text")
		}
		current.Multiline = nil

		// Look for start of new check.
		switch what {
		case "GET", "HEAD", "POST":
			if !lastLineWasBlank {
				return nil, errorf("missing blank line before start of case")
			}
			if args == "" {
				return nil, errorf("missing %s URL", what)
			}
			cas := &case_{method: what, url: args, file: file, line: lineno}
			script.cases = append(script.cases, cas)
			current.Case = cas
			lastLineWasBlank = false
			continue
		}

		if lastLineWasBlank || current.Case == nil {
			return nil, errorf("missing GET/HEAD/POST at start of check")
		}

		// Look for case metadata.
		var targ *string
		switch what {
		case "postbody":
			targ = &current.Case.postbody
		case "postquery":
			targ = &current.Case.postquery
		case "posttype":
			targ = &current.Case.posttype
		case "hint":
			targ = &current.Case.hint
		}
		if targ != nil {
			if strings.HasPrefix(what, "post") && current.Case.method != "POST" {
				return nil, errorf("need POST (not %v) for %v", current.Case.method, what)
			}
			if args != "" {
				*targ = args
			} else {
				current.Multiline = targ
			}
			continue
		}

		// Start a comparison check.
		chk := &cmpCheck{file: file, line: lineno, what: what}
		current.Case.checks = append(current.Case.checks, chk)
		switch what {
		case "body", "code", "redirect":
			// no WhatArg
		case "header":
			chk.whatArg, args = splitOneField(args)
			if chk.whatArg == "" {
				return nil, errorf("missing header name")
			}
		}

		// Opcode, with optional leading "not"
		chk.op, args = splitOneField(args)
		switch chk.op {
		case "==", "!=", "~", "!~", "contains", "!contains":
			// ok
		default:
			return nil, errorf("unknown check operator %q", chk.op)
		}

		if args != "" {
			chk.want = args
		} else {
			current.Multiline = &chk.want
		}
	}

	// Finish each case.
	// Compute POST body from POST query.
	// Check that each regexp compiles, and insert "code equals 200"
	// in each case that doesn't already have a code check.
	for _, cas := range script.cases {
		if cas.postquery != "" {
			if cas.postbody != "" {
				line = ""
				lineno = cas.line
				return nil, errorf("case has postbody and postquery")
			}
			for _, kv := range strings.Split(cas.postquery, "\n") {
				kv = strings.TrimSpace(kv)
				if kv == "" {
					continue
				}
				k, v, ok := cut(kv, "=")
				if !ok {
					lineno = cas.line // close enough
					line = kv
					return nil, errorf("postquery has non key=value line")
				}
				if cas.postbody != "" {
					cas.postbody += "&"
				}
				cas.postbody += url.QueryEscape(k) + "=" + url.QueryEscape(v)
			}
		}
		sawCode := false
		for _, chk := range cas.checks {
			if chk.what == "code" || chk.what == "redirect" {
				sawCode = true
			}
			if chk.op == "~" || chk.op == "!~" {
				re, err := regexp.Compile(`(?m)` + chk.want)
				if err != nil {
					lineno = chk.line
					line = chk.want
					return nil, errorf("invalid regexp: %s", err)
				}
				chk.wantRE = re
			}
		}
		if !sawCode {
			line := cas.line
			if len(cas.checks) > 0 {
				line = cas.checks[0].line
			}
			chk := &cmpCheck{file: cas.file, line: line, what: "code", op: "==", want: "200"}
			cas.checks = append(cas.checks, chk)
		}
	}
	return script, nil
}