feat: add commit body check

Signed-off-by: Andrew Rynhard <andrew@andrewrynhard.com>

internal/policy/commit/check_body.go

@@ -0,0 +1,64 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package commit
+
+import (
+	"strings"
+
+	"github.com/autonomy/conform/internal/policy"
+	"github.com/pkg/errors"
+)
+
+// RequiredBodyThreshold is the default minimum number of line changes required
+// to trigger the body check.
+var RequiredBodyThreshold = 10
+
+// Body enforces a maximum number of charcters on the commit
+// header.
+type Body struct {
+	errors []error
+}
+
+// Name returns the name of the check.
+func (h Body) Name() string {
+	return "Commit Body"
+}
+
+// Message returns to check message.
+func (h Body) Message() string {
+	return "Commit body is valid"
+}
+
+// Errors returns any violations of the check.
+func (h Body) Errors() []error {
+	return h.errors
+}
+
+// ValidateBody checks the header length.
+func (c Commit) ValidateBody() policy.Check {
+	check := &Body{}
+
+	if c.HeaderLength != 0 {
+		MaxNumberOfCommitCharacters = c.HeaderLength
+	}
+
+	lines := strings.Split(strings.TrimPrefix(c.msg, "\n"), "\n")
+	valid := false
+	for _, line := range lines[1:] {
+		if DCORegex.MatchString(strings.TrimSpace(line)) {
+			continue
+		}
+		if line != "" {
+			valid = true
+			break
+		}
+	}
+
+	if !valid {
+		check.errors = append(check.errors, errors.New("Commit body is empty"))
+	}
+
+	return check
+}

internal/policy/commit/commit.go

@@ -29,6 +29,8 @@ type Commit struct {
 	// MaximumOfOneCommit enforces that the current commit is only one commit
 	// ahead of a specified ref.
 	MaximumOfOneCommit bool `mapstructure:"maximumOfOneCommit"`
+	// RequireCommitBody enforces that the current commit has a body.
+	RequireCommitBody bool `mapstructure:"requireCommitBody"`
 	// Conventional is the user specified settings for conventional commits.
 	Conventional *Conventional `mapstructure:"conventional"`
 
@@ -89,6 +91,10 @@ func (c *Commit) Compliance(options *policy.Options) (*policy.Report, error) {
 		report.AddCheck(c.ValidateNumberOfCommits(g, "refs/heads/master"))
 	}
 
+	if c.RequireCommitBody {
+		report.AddCheck(c.ValidateBody())
+	}
+
 	return report, nil
 }