GitExtensions/GitCommands/CommitInformation.cs

using System;
using System.Collections.Generic;
using System.Text;

namespace GitCommands
{
    public class CommitInformation
    {
        /// <summary>
        /// Private constructor
        /// </summary>
        private CommitInformation (string header, string body)
        {
            Header = header;
            Body = body;
        }

        public string Header {get; private set;}
        public string Body{get; private set;}

        /// <summary>
        /// Gets branches which contain the given commit.
        /// If both local and remote branches are requested, remote branches are prefixed with "remotes/"
        /// (as returned by git branch -a)
        /// </summary>
        /// <param name="sha1">The sha1.</param>
        /// <param name="getLocal">Pass true to include local branches</param>
        /// <param name="getLocal">Pass true to include remote branches</param>
        /// <returns></returns>
        public static IEnumerable<string> GetAllBranchesWhichContainGivenCommit(string sha1, bool getLocal, bool getRemote) 
        {
            string args = "--contains " + sha1;
            if (getRemote && getLocal)
                args = "-a "+args;
            else if (getRemote)
                args = "-r "+args;
            else if (!getLocal)
                return new string[]{};
            string info = GitCommandHelpers.RunCmd(Settings.GitCommand, "branch "+args);
            if (info.Trim().StartsWith("fatal") || info.Trim().StartsWith("error:"))
                return new List<string>();

            string[] result = info.Split(new[] { '\r', '\n', '*' }, StringSplitOptions.RemoveEmptyEntries);

            // Remove symlink targets as in "origin/HEAD -> origin/master"
            for (int i = 0; i < result.Length; i++)
            {
                string item = result[i].Trim();
                int idx;
                if (getRemote && ((idx = item.IndexOf(" ->")) >= 0))
                {
                    item = item.Substring(0, idx);
                }
                result[i] = item;
            }

            return result;
        }

        /// <summary>
        /// Gets all tags which contain the given commit.
        /// </summary>
        /// <param name="sha1">The sha1.</param>
        /// <returns></returns>
        public static IEnumerable<string> GetAllTagsWhichContainGivenCommit(string sha1)
        {
            string info = GitCommandHelpers.RunCmd(Settings.GitCommand, "tag --contains " + sha1);


            if (info.Trim().StartsWith("fatal") || info.Trim().StartsWith("error:"))
                return new List<string>();
            return info.Split(new[] { '\r', '\n', '*', ' ' }, StringSplitOptions.RemoveEmptyEntries);
        }

        /// <summary>
        /// Gets the commit info.
        /// </summary>
        /// <param name="sha1">The sha1.</param>
        /// <returns></returns>
        public static CommitInformation GetCommitInfo(string sha1)
        {
            string info = GitCommandHelpers.RunCachableCmd(
                Settings.GitCommand,
                string.Format(
                    "show -s --pretty=format:\"{0}:\t\t%aN (%aE)%n{1}:\t%ar (%ad)%n{2}:\t%cN (%cE)%n{3}:\t%cr (%cd)%n{4}:\t%H%n%n%s%n%n%b\" {5}",
                    Strings.GetAuthorText(),
                    Strings.GetAuthorDateText(),
                    Strings.GetCommitterText(),
                    Strings.GetCommitterDateText(),
                    Strings.GetCommitHashText(), sha1));

            if (info.Trim().StartsWith("fatal"))
                return new CommitInformation("Cannot find commit" + sha1, "");

            info = RemoveRedundancies(info);

            int index = info.IndexOf(sha1) + sha1.Length;

            if (index < 0)
                return new CommitInformation("Cannot find commit" + sha1, "");
            if (index >= info.Length)
                return new CommitInformation(info, "");

            string commitHeader = info.Substring(0, index);
            string commitMessage = info.Substring(index);

            //We need to recode the commit message because of a bug in Git.
            //We cannot let git recode the message to Settings.Encoding which is
            //needed to allow the "git log" to print the filename in Settings.Encoding
            Encoding logoutputEncoding = GitCommandHelpers.GetLogoutputEncoding();
            if (logoutputEncoding != Settings.Encoding)
                commitMessage = logoutputEncoding.GetString(Settings.Encoding.GetBytes(commitMessage));

            return new CommitInformation(commitHeader,
                                         commitMessage);
        }

        private static string RemoveRedundancies(string info)
        {
            string author = GetField(info, Strings.GetAuthorText() + ":");
            string committer = GetField(info, Strings.GetCommitterText() + ":");

            if (String.Equals(author, committer, StringComparison.CurrentCulture))
            {
                info = RemoveField(info, Strings.GetCommitterText() + ":");
            }

            string authorDate = GetField(info, Strings.GetAuthorDateText() + ":");
            string commitDate = GetField(info, Strings.GetCommitterDateText() + ":");

            if (String.Equals(authorDate, commitDate, StringComparison.CurrentCulture))
            {
                info =
                    RemoveField(info, Strings.GetCommitterDateText() + ":").Replace(
                        Strings.GetAuthorDateText() + ":\t", Strings.GetDateText() + ":\t\t");
            }

            return info;
        }

        private static string RemoveField(string data, string header)
        {
            int headerIndex = data.IndexOf(header);

            if (headerIndex == -1)
                return data;

            int endIndex = data.IndexOf('\n', headerIndex);

            if (endIndex == -1)
                endIndex = data.Length - 1;

            int length = endIndex - headerIndex + 1;

            return data.Remove(headerIndex, length);
        }

        private static string GetField(string data, string header)
        {
            int valueIndex = IndexOfValue(data, header);

            if (valueIndex == -1)
                return null;

            int length = LengthOfValue(data, valueIndex);
            return data.Substring(valueIndex, length);
        }

        private static int LengthOfValue(string data, int valueIndex)
        {
            if (valueIndex == -1)
                return 0;

            int endIndex = data.IndexOf('\n', valueIndex);

            if (endIndex == -1)
                endIndex = data.Length - 1;

            return endIndex - valueIndex;
        }

        private static int IndexOfValue(string data, string header)
        {
            int headerIndex = data.IndexOf(header);

            if (headerIndex == -1)
                return -1;

            int valueIndex = headerIndex + header.Length;

            while (data[valueIndex] == '\t')
            {
                valueIndex++;

                if (valueIndex == data.Length)
                    return -1;
            }

            return valueIndex;
        }
    }
}