add git merge

ide-former-plugin/ide-core/src/main/kotlin/org/jetbrains/research/ideFormerPlugin/api/models/gitRelated/GitMerge.kt

@@ -0,0 +1,20 @@
+package org.jetbrains.research.ideFormerPlugin.api.models.gitRelated
+
+import com.intellij.openapi.project.Project
+import com.intellij.openapi.vfs.VirtualFile
+import git4idea.commands.GitCommand
+
+class GitMerge(
+    project: Project,
+    projectGitRoot: VirtualFile,
+    mergingBranchName: String
+) : GitApiMethod(project, projectGitRoot) {
+    // Invariant: you're staying on the right branch that you want to merge changes to. Git checkout was made recently.
+    override var gitCommand: GitCommand? = GitCommand.MERGE
+    override var gitCommandParameters: List<String>? = listOf(mergingBranchName)
+
+    override var gitReverseCommand: GitCommand? = GitCommand.RESET
+    // --merge as opposed to the --hard doesn't reset uncommited/ unstashed files.
+    // ORIG_HEAD will point to a commit directly before merge has occurred, so you don't have to hunt for it by yourself.
+    override var gitReverseCommandParameters: List<String>? = listOf("--merge", "ORIG_HEAD")
+}

ide-former-plugin/ide-core/src/main/kotlin/org/jetbrains/research/ideFormerPlugin/api/models/utils/GitUtils.kt

@@ -9,7 +9,7 @@ fun executeGitCommand(
     projectGitRoot: VirtualFile,
     gitCommand: GitCommand,
     gitCommandParameters: List<String>?
-) : String {
+): String {
     val git = Git.getInstance()
 
     val gitCommandHandler = GitLineHandler(project, projectGitRoot, gitCommand)

ide-former-plugin/ide-server/src/main/kotlin/org/jetbrains/research/ideFormerPlugin/server/Routing.kt

@@ -41,6 +41,7 @@ fun Application.configureRouting(ideStateKeeper: IdeStateKeeper, logger: Logger)
         getGitReset(logger, ideStateKeeper)
         getGitBranch(logger, ideStateKeeper)
         getGitCheckout(logger, ideStateKeeper)
+        getGitMerge(logger, ideStateKeeper)
     }
 }
 

ide-former-plugin/ide-server/src/main/kotlin/org/jetbrains/research/ideFormerPlugin/server/requests/gitRelated/getGitMerge.kt

@@ -0,0 +1,25 @@
+package org.jetbrains.research.ideFormerPlugin.server.requests.gitRelated
+
+import io.ktor.server.application.*
+import io.ktor.server.routing.*
+import org.jetbrains.research.ideFormerPlugin.api.models.gitRelated.GitMerge
+import org.jetbrains.research.ideFormerPlugin.server.*
+import org.jetbrains.research.ideFormerPlugin.stateKeeper.IdeStateKeeper
+import org.slf4j.Logger
+
+fun Routing.getGitMerge(logger: Logger, ideStateKeeper: IdeStateKeeper) {
+    get("/git-merge/{${IdeServerConstants.BRANCH_NAME_REQUEST_PARAM}?}") {
+        val mergingBranchName = call.processRequestParameter(IdeServerConstants.BRANCH_NAME_REQUEST_PARAM, logger)
+            ?: return@get
+        logger.info("Server GET git merge $mergingBranchName into current branch is called")
+
+        val gitMerge = GitMerge(ideStateKeeper.userProject, ideStateKeeper.projectGitRoot, mergingBranchName)
+        if (!executeAndRespondError(gitMerge, logger)) return@get
+
+        ideStateKeeper.saveReversibleApiMethod(gitMerge)
+        logger.info("Git merge api method was saved on the api methods stack")
+
+        call.respondJson("Git merge $mergingBranchName into current branch was processed successfully")
+        logger.info("Server GET git merge $mergingBranchName into current branch is processed")
+    }
+}

ide-former-plugin/ide-server/src/main/resources/org/jetbrains/research/ideFormerPlugin/server/ideApiDescriptions.json

@@ -232,6 +232,21 @@
     ],
     "optional_parameters": []
   },
+  {
+    "name": "git_merge",
+    "url": "/git-merge",
+    "description": "Merge commits from the given branch to the current branch of a Git repository.",
+    "method": "GET",
+    "required_parameters": [
+      {
+        "name": "branchName",
+        "type": "STRING",
+        "regex": "[A-Za-z]*",
+        "description": "The name of a branch that should be merged to the current branch of a Git repository."
+      }
+    ],
+    "optional_parameters": []
+  },
   {
     "name": "reverse_last_api_methods",
     "url": "/reverse-api-methods",