name_pattern.go

1	package main
2
3	import (
4	"errors"
5	"fmt"
6	"strings"
7	"text/template"
8	"time"
9	)
10
11	func createNewNameForPatterns(
12	now time.Time,
13	patternData PrePatternData,
14	projectName string,
15	namePatterns []ParameterizedText,
16	extras map[string]string,
17	validator func(newName string) bool) (string, error) {
18	for index, namePattern := range namePatterns {
19
20	startingVersion := 1
21	invokeCount := 0
22	funcMap := template.FuncMap{
23	"getVersion": func() int {
24	invokeCount++
25	return startingVersion
26	},
27	}
28	template := template.New("template-name").Funcs(funcMap)
29
30	for {
31
32	template, err := template.Parse(string(namePattern))
33	if err != nil {
34	return "", fmt.Errorf("error parsing name pattern %d: %w", index, err)
35	}
36
37	sb := new(strings.Builder)
38	err = template.Execute(sb, patternData)
39	if err != nil {
40	return "", fmt.Errorf("error executing name pattern %d: %w", index, err)
41	}
42
43	newName := sb.String()
44	isValid := validator(newName)
45	useIndex := invokeCount > 0
46	isLastPattern := index == len(namePatterns)-1
47
48	// if new name is valid, use this name
49	if isValid {
50	return newName, nil
51	}
52
53	// if index is not being used (template did not invoke getVersion)
54	// then we're done
55	if !useIndex {
56	break
57	}
58
59	// if getVersion was used, but this isn't the last pattern, report an error
60	if useIndex && !isLastPattern {
61	return "", errors.New("cannot use function getVersion in a pattern that is not the last pattern")
62	}
63
64	startingVersion++
65	}
66	}
67	return "", errors.New("couldn't find a new name")
68	}