drone/git/command/parser.go

124 lines
2.4 KiB
Go

// Copyright 2023 Harness, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package command
import (
"strings"
)
// Parse os args to Command object.
// This is very basic parser which doesn't care about
// flags or positional args values it just injects into proper
// slice of command struct. Every git command can contain
// globals:
//
// git --help
//
// command:
//
// git version
// git diff
//
// action:
//
// git remote set-url ...
//
// command or action flags:
//
// git diff --shortstat
//
// command or action args:
//
// git diff --shortstat main...dev
//
// post args:
//
// git diff main...dev -- file1
func Parse(args ...string) *Command {
actions := map[string]uint{}
c := &Command{}
globalPos := -1
namePos := -1
actionPos := -1
flagsPos := -1
argsPos := -1
postPos := -1
if len(args) == 0 {
return c
}
if strings.ToLower(args[0]) == "git" {
args = args[1:]
}
for i, arg := range args {
isFlag := arg != "--" && strings.HasPrefix(arg, "-")
b, isCommand := descriptions[arg]
_, isAction := actions[arg]
switch {
case globalPos == -1 && namePos == -1 && isFlag:
globalPos = i
case namePos == -1 && isCommand:
namePos = i
actions = b.actions
case actionPos == -1 && isAction && !isFlag:
actionPos = i
case flagsPos == -1 && (namePos >= 0 || actionPos > 0) && isFlag:
flagsPos = i
case argsPos == -1 && (namePos >= 0 || actionPos > 0) && !isFlag:
argsPos = i
case postPos == -1 && arg == "--":
postPos = i
}
}
end := len(args)
if globalPos >= 0 {
c.Globals = args[globalPos:cmpPos(namePos, end)]
}
if namePos >= 0 {
c.Name = args[namePos]
}
if actionPos > 0 {
c.Action = args[actionPos]
}
if flagsPos > 0 {
c.Flags = args[flagsPos:cmpPos(argsPos, end)]
}
if argsPos > 0 {
c.Args = args[argsPos:cmpPos(postPos, end)]
}
if postPos > 0 {
c.PostSepArgs = args[postPos+1:]
}
return c
}
func cmpPos(check, or int) int {
if check == -1 {
return or
}
return check
}