From 9a46a6e58f422ae1eb3257b805d6a9968eedec86 Mon Sep 17 00:00:00 2001
From: Charlie Collard <charliecollard0@gmail.com>
Date: Wed, 22 Sep 2021 22:48:02 +0100
Subject: [PATCH] Add `require_linear_history` on `github_branch_protection`
 resource (#887)

* Add `require_linear_history` on `github_branch_protection` resource

* Run gofmt

* Move documentation to correct file
---
 github/resource_github_branch_protection.go    | 10 ++++++++++
 github/util_v4_branch_protection.go            |  6 ++++++
 github/util_v4_consts.go                       |  1 +
 website/docs/r/branch_protection.html.markdown |  1 +
 4 files changed, 18 insertions(+)

diff --git a/github/resource_github_branch_protection.go b/github/resource_github_branch_protection.go
index 74f16abb55..1f99a3db5a 100644
--- a/github/resource_github_branch_protection.go
+++ b/github/resource_github_branch_protection.go
@@ -48,6 +48,11 @@ func resourceGithubBranchProtection() *schema.Resource {
 				Optional: true,
 				Default:  false,
 			},
+			PROTECTION_REQUIRES_LINEAR_HISTORY: {
+				Type:     schema.TypeBool,
+				Optional: true,
+				Default:  false,
+			},
 			PROTECTION_REQUIRES_APPROVING_REVIEWS: {
 				Type:     schema.TypeList,
 				Optional: true,
@@ -217,6 +222,11 @@ func resourceGithubBranchProtectionRead(d *schema.ResourceData, meta interface{}
 		log.Printf("[WARN] Problem setting '%s' in %s %s branch protection (%s)", PROTECTION_REQUIRES_COMMIT_SIGNATURES, protection.Repository.Name, protection.Pattern, d.Id())
 	}
 
+	err = d.Set(PROTECTION_REQUIRES_LINEAR_HISTORY, protection.RequiresLinearHistory)
+	if err != nil {
+		log.Printf("[WARN] Problem setting '%s' in %s %s branch protection (%s)", PROTECTION_REQUIRES_LINEAR_HISTORY, protection.Repository.Name, protection.Pattern, d.Id())
+	}
+
 	approvingReviews := setApprovingReviews(protection)
 	err = d.Set(PROTECTION_REQUIRES_APPROVING_REVIEWS, approvingReviews)
 	if err != nil {
diff --git a/github/util_v4_branch_protection.go b/github/util_v4_branch_protection.go
index 73bda828fd..e3f43aa61c 100644
--- a/github/util_v4_branch_protection.go
+++ b/github/util_v4_branch_protection.go
@@ -50,6 +50,7 @@ type BranchProtectionRule struct {
 	RequiresApprovingReviews     githubv4.Boolean
 	RequiresCodeOwnerReviews     githubv4.Boolean
 	RequiresCommitSignatures     githubv4.Boolean
+	RequiresLinearHistory        githubv4.Boolean
 	RequiresStatusChecks         githubv4.Boolean
 	RequiresStrictStatusChecks   githubv4.Boolean
 	RestrictsPushes              githubv4.Boolean
@@ -70,6 +71,7 @@ type BranchProtectionResourceData struct {
 	RequiresApprovingReviews     bool
 	RequiresCodeOwnerReviews     bool
 	RequiresCommitSignatures     bool
+	RequiresLinearHistory        bool
 	RequiresStatusChecks         bool
 	RequiresStrictStatusChecks   bool
 	RestrictsPushes              bool
@@ -108,6 +110,10 @@ func branchProtectionResourceData(d *schema.ResourceData, meta interface{}) (Bra
 		data.RequiresCommitSignatures = v.(bool)
 	}
 
+	if v, ok := d.GetOk(PROTECTION_REQUIRES_LINEAR_HISTORY); ok {
+		data.RequiresLinearHistory = v.(bool)
+	}
+
 	if v, ok := d.GetOk(PROTECTION_REQUIRES_APPROVING_REVIEWS); ok {
 		vL := v.([]interface{})
 		if len(vL) > 1 {
diff --git a/github/util_v4_consts.go b/github/util_v4_consts.go
index fc4a88d8bc..b4a4bc6d67 100644
--- a/github/util_v4_consts.go
+++ b/github/util_v4_consts.go
@@ -11,6 +11,7 @@ const (
 	PROTECTION_REQUIRES_APPROVING_REVIEWS      = "required_pull_request_reviews"
 	PROTECTION_REQUIRES_CODE_OWNER_REVIEWS     = "require_code_owner_reviews"
 	PROTECTION_REQUIRES_COMMIT_SIGNATURES      = "require_signed_commits"
+	PROTECTION_REQUIRES_LINEAR_HISTORY         = "required_linear_history"
 	PROTECTION_REQUIRES_STATUS_CHECKS          = "required_status_checks"
 	PROTECTION_REQUIRES_STRICT_STATUS_CHECKS   = "strict"
 	PROTECTION_RESTRICTS_PUSHES                = "push_restrictions"
diff --git a/website/docs/r/branch_protection.html.markdown b/website/docs/r/branch_protection.html.markdown
index 013425b385..7ff6ded8bd 100644
--- a/website/docs/r/branch_protection.html.markdown
+++ b/website/docs/r/branch_protection.html.markdown
@@ -76,6 +76,7 @@ The following arguments are supported:
 * `pattern` - (Required) Identifies the protection rule pattern.
 * `enforce_admins` - (Optional) Boolean, setting this to `true` enforces status checks for repository administrators.
 * `require_signed_commits` - (Optional) Boolean, setting this to `true` requires all commits to be signed with GPG.
+* `required_linear_history` - (Optional) Boolean, setting this to `true` enforces a linear commit Git history, which prevents anyone from pushing merge commits to a branch
 * `required_status_checks` - (Optional) Enforce restrictions for required status checks. See [Required Status Checks](#required-status-checks) below for details.
 * `required_pull_request_reviews` - (Optional) Enforce restrictions for pull request reviews. See [Required Pull Request Reviews](#required-pull-request-reviews) below for details.
 * `push_restrictions` - (Optional) The list of actor IDs that may push to the branch.