diff --git a/git/commits.go b/git/commits.go
index aad1039..0084877 100644
--- a/git/commits.go
+++ b/git/commits.go
@@ -2,9 +2,6 @@ package git
 
 import (
 	"bytes"
-	"encoding/json"
-	"fmt"
-	"log"
 	"os"
 	"os/exec"
 	"strings"
@@ -16,7 +13,7 @@ import (
 // If commitrange is a git still range 12345...54321, then it will be isolated set of commits.
 // If commitrange is a single commit, all ancestor commits up through the hash provided.
 func Commits(commitrange string) ([]CommitEntry, error) {
-	cmdArgs := []string{"git", "log", prettyFormat + formatCommit, commitrange}
+	cmdArgs := []string{"git", "log", `--pretty=format:%H`, commitrange}
 	if debug() {
 		logrus.Infof("[git] cmd: %q", strings.Join(cmdArgs, " "))
 	}
@@ -36,61 +33,47 @@ func Commits(commitrange string) ([]CommitEntry, error) {
 	return commits, nil
 }
 
-// CommitEntry represents a single commit's information from `git`
-type CommitEntry map[string]string
+// FieldNames are for the formating and rendering of the CommitEntry structs.
+// Keys here are from git log pretty format "format:..."
+var FieldNames = map[string]string{
+	"%h":  "abbreviated_commit",
+	"%p":  "abbreviated_parent",
+	"%t":  "abbreviated_tree",
+	"%aD": "author_date",
+	"%aE": "author_email",
+	"%aN": "author_name",
+	"%b":  "body",
+	"%H":  "commit",
+	"%N":  "commit_notes",
+	"%cD": "committer_date",
+	"%cE": "committer_email",
+	"%cN": "committer_name",
+	"%e":  "encoding",
+	"%P":  "parent",
+	"%D":  "refs",
+	"%f":  "sanitized_subject_line",
+	"%GS": "signer",
+	"%GK": "signer_key",
+	"%s":  "subject",
+	"%G?": "verification_flag",
+}
 
-var (
-	prettyFormat         = `--pretty=format:`
-	formatSubject        = `%s`
-	formatBody           = `%b`
-	formatCommit         = `%H`
-	formatAuthorName     = `%aN`
-	formatAuthorEmail    = `%aE`
-	formatCommitterName  = `%cN`
-	formatCommitterEmail = `%cE`
-	formatSigner         = `%GS`
-	formatCommitNotes    = `%N`
-	formatMap            = `{"commit": "%H", "abbreviated_commit": "%h", "tree": "%T", "abbreviated_tree": "%t", "parent": "%P", "abbreviated_parent": "%p", "refs": "%D", "encoding": "%e", "sanitized_subject_line": "%f", "verification_flag": "%G?", "signer_key": "%GK", "author_date": "%aD" , "committer_date": "%cD" }`
-)
+// CommitEntry represents a single commit's information from `git`.
+// See also FieldNames
+type CommitEntry map[string]string
 
 // LogCommit assembles the full information on a commit from its commit hash
 func LogCommit(commit string) (*CommitEntry, error) {
 	buf := bytes.NewBuffer([]byte{})
-	cmdArgs := []string{"git", "log", "-1", prettyFormat + formatMap, commit}
-	if debug() {
-		logrus.Infof("[git] cmd: %q", strings.Join(cmdArgs, " "))
-	}
-	cmd := exec.Command(cmdArgs[0], cmdArgs[1:]...)
-	cmd.Stdout = buf
-	cmd.Stderr = os.Stderr
-
-	if err := cmd.Run(); err != nil {
-		log.Println(strings.Join(cmd.Args, " "))
-		return nil, err
-	}
 	c := CommitEntry{}
-	output := buf.Bytes()
-	if err := json.Unmarshal(output, &c); err != nil {
-		fmt.Println(string(output))
-		return nil, err
-	}
-
-	// any user provided fields can't be sanitized for the mock-json marshal above
-	for k, v := range map[string]string{
-		"subject":         formatSubject,
-		"body":            formatBody,
-		"author_name":     formatAuthorName,
-		"author_email":    formatAuthorEmail,
-		"committer_name":  formatCommitterName,
-		"committer_email": formatCommitterEmail,
-		"commit_notes":    formatCommitNotes,
-		"signer":          formatSigner,
-	} {
-		output, err := exec.Command("git", "log", "-1", prettyFormat+v, commit).Output()
-		if err != nil {
+	for k, v := range FieldNames {
+		cmd := exec.Command("git", "log", "-1", `--pretty=format:`+k+``, commit)
+		cmd.Stdout = buf
+		cmd.Stderr = os.Stderr
+		if err := cmd.Run(); err != nil {
 			return nil, err
 		}
-		c[k] = strings.TrimSpace(string(output))
+		c[v] = strings.TrimSpace(string(buf.Bytes()))
 	}
 
 	return &c, nil
diff --git a/git/commits_test.go b/git/commits_test.go
new file mode 100644
index 0000000..0194934
--- /dev/null
+++ b/git/commits_test.go
@@ -0,0 +1,55 @@
+package git
+
+import (
+	"encoding/json"
+	"io/ioutil"
+	"testing"
+)
+
+func TestCommitEntry(t *testing.T) {
+	c, err := HeadCommit()
+	if err != nil {
+		t.Fatal(err)
+	}
+	cr, err := Commits(c)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, c := range cr {
+		for _, cV := range FieldNames {
+			found := false
+			for k := range c {
+				if k == cV {
+					found = true
+				}
+			}
+			if !found {
+				t.Errorf("failed to find field names: %q", c)
+			}
+		}
+	}
+}
+
+func TestMarshal(t *testing.T) {
+	buf, err := ioutil.ReadFile("testdata/commits.json")
+	if err != nil {
+		t.Fatal(err)
+	}
+	cr := []CommitEntry{}
+	if err := json.Unmarshal(buf, &cr); err != nil {
+		t.Error(err)
+	}
+	for _, c := range cr {
+		for _, cV := range FieldNames {
+			found := false
+			for k := range c {
+				if k == cV {
+					found = true
+				}
+			}
+			if !found {
+				t.Errorf("failed to find field names: %q", c)
+			}
+		}
+	}
+}
diff --git a/git/testdata/commits.json b/git/testdata/commits.json
new file mode 100644
index 0000000..7735912
--- /dev/null
+++ b/git/testdata/commits.json
@@ -0,0 +1 @@
+[{"abbreviated_commit":"769b402","abbreviated_parent":"eba7575","abbreviated_tree":"f3490fa","author_date":"Thu, 14 Jan 2016 10:29:35 -0500","author_email":"vbatts@hashbangbash.com","author_name":"Vincent Batts","body":"so you can test and just check return code\n\nSigned-off-by: Vincent Batts \u003cvbatts@hashbangbash.com\u003e","commit":"769b4028a4732f5134848aa970e73e2d6edc3175","commit_notes":"","committer_date":"Thu, 14 Jan 2016 10:29:35 -0500","committer_email":"vbatts@hashbangbash.com","committer_name":"Vincent Batts","encoding":"","parent":"eba7575f7eccc9ee1aa5874769b44a62b612947d","refs":"HEAD -\u003e master, origin/master, origin/HEAD","sanitized_subject_line":"main-adding-a-quiet-flag-to-reduce-the-output","signer":"","signer_key":"","subject":"main: adding a quiet flag to reduce the output","tree":"f3490fa57c956658a78348651bf75dfad15e5f68","verification_flag":"N"},{"abbreviated_commit":"eba7575","abbreviated_parent":"09c2bd4","abbreviated_tree":"77c40ce","author_date":"Tue, 6 Oct 2015 10:55:42 -0400","author_email":"vbatts@hashbangbash.com","author_name":"Vincent Batts","body":"Signed-off-by: Vincent Batts \u003cvbatts@hashbangbash.com\u003e","commit":"eba7575f7eccc9ee1aa5874769b44a62b612947d","commit_notes":"","committer_date":"Tue, 6 Oct 2015 10:55:42 -0400","committer_email":"vbatts@hashbangbash.com","committer_name":"Vincent Batts","encoding":"","parent":"09c2bd43dc6f0508f461f9e1088013abbd3fa3d5","refs":"","sanitized_subject_line":"README-information-about-rules","signer":"","signer_key":"","subject":"README: information about rules","tree":"77c40ce1580d215d8cac2d997d41d08baa6b2546","verification_flag":"N"},{"abbreviated_commit":"09c2bd4","abbreviated_parent":"b243ca4","abbreviated_tree":"f88ab5a","author_date":"Tue, 6 Oct 2015 10:51:22 -0400","author_email":"vbatts@hashbangbash.com","author_name":"Vincent Batts","body":"Signed-off-by: Vincent Batts \u003cvbatts@hashbangbash.com\u003e","commit":"09c2bd43dc6f0508f461f9e1088013abbd3fa3d5","commit_notes":"","committer_date":"Tue, 6 Oct 2015 10:51:22 -0400","committer_email":"vbatts@hashbangbash.com","committer_name":"Vincent Batts","encoding":"","parent":"b243ca47707576f7551094dd26c8e4647f093acf","refs":"","sanitized_subject_line":"README-more-usage","signer":"","signer_key":"","subject":"README: more usage","tree":"f88ab5a60a21f177e37b7eee3ee7c2c0e15f0892","verification_flag":"N"},{"abbreviated_commit":"b243ca4","abbreviated_parent":"d614ccf","abbreviated_tree":"a0c3f0b","author_date":"Tue, 6 Oct 2015 10:47:00 -0400","author_email":"vbatts@hashbangbash.com","author_name":"Vincent Batts","body":"Signed-off-by: Vincent Batts \u003cvbatts@hashbangbash.com\u003e","commit":"b243ca47707576f7551094dd26c8e4647f093acf","commit_notes":"","committer_date":"Tue, 6 Oct 2015 10:48:03 -0400","committer_email":"vbatts@hashbangbash.com","committer_name":"Vincent Batts","encoding":"","parent":"d614ccf9970296e9619e28883748be653801dbf3","refs":"","sanitized_subject_line":"README-adding-install-and-usage","signer":"","signer_key":"","subject":"README: adding install and usage","tree":"a0c3f0b74f503938d7d7c31a5d6e937410d520ae","verification_flag":"N"},{"abbreviated_commit":"d614ccf","abbreviated_parent":"b9413c6","abbreviated_tree":"785f2f5","author_date":"Tue, 6 Oct 2015 10:44:04 -0400","author_email":"vbatts@hashbangbash.com","author_name":"Vincent Batts","body":"for cleanliness and ease of testing\n\nSigned-off-by: Vincent Batts \u003cvbatts@hashbangbash.com\u003e","commit":"d614ccf9970296e9619e28883748be653801dbf3","commit_notes":"","committer_date":"Tue, 6 Oct 2015 10:44:04 -0400","committer_email":"vbatts@hashbangbash.com","committer_name":"Vincent Batts","encoding":"","parent":"b9413c60c83d6f25d8979292d09ddceff0cde111","refs":"","sanitized_subject_line":"run-tests-in-a-runner","signer":"","signer_key":"","subject":"*: run tests in a runner","tree":"785f2f51a0e92f590053745be8e915116e4e8c59","verification_flag":"N"},{"abbreviated_commit":"b9413c6","abbreviated_parent":"5e74abd","abbreviated_tree":"997fcb4","author_date":"Mon, 5 Oct 2015 19:02:31 -0400","author_email":"vbatts@hashbangbash.com","author_name":"Vincent Batts","body":"Signed-off-by: Vincent Batts \u003cvbatts@hashbangbash.com\u003e","commit":"b9413c60c83d6f25d8979292d09ddceff0cde111","commit_notes":"","committer_date":"Mon, 5 Oct 2015 19:02:31 -0400","committer_email":"vbatts@hashbangbash.com","committer_name":"Vincent Batts","encoding":"","parent":"5e74abd1b2560d91647280da8374978763cb3b0f","refs":"","sanitized_subject_line":"shortsubject-add-a-subject-length-check","signer":"","signer_key":"","subject":"shortsubject: add a subject length check","tree":"997fcb4cf30c0f25ac5feb907ff5a977b8a65ae6","verification_flag":"N"},{"abbreviated_commit":"5e74abd","abbreviated_parent":"07a982f","abbreviated_tree":"6605800","author_date":"Mon, 5 Oct 2015 18:55:05 -0400","author_email":"vbatts@hashbangbash.com","author_name":"Vincent Batts","body":"Signed-off-by: Vincent Batts \u003cvbatts@hashbangbash.com\u003e","commit":"5e74abd1b2560d91647280da8374978763cb3b0f","commit_notes":"","committer_date":"Mon, 5 Oct 2015 18:55:05 -0400","committer_email":"vbatts@hashbangbash.com","committer_name":"Vincent Batts","encoding":"","parent":"07a982ff94318262732e6422daa75f1f51340b60","refs":"","sanitized_subject_line":"comments-and-golint","signer":"","signer_key":"","subject":"*: comments and golint","tree":"6605800cc08fc9906b9ab9819413d2adaffd0ed5","verification_flag":"N"},{"abbreviated_commit":"07a982f","abbreviated_parent":"03bda4b","abbreviated_tree":"8a81024","author_date":"Mon, 5 Oct 2015 18:45:33 -0400","author_email":"vbatts@hashbangbash.com","author_name":"Vincent Batts","body":"Signed-off-by: Vincent Batts \u003cvbatts@hashbangbash.com\u003e","commit":"07a982ff94318262732e6422daa75f1f51340b60","commit_notes":"","committer_date":"Mon, 5 Oct 2015 18:49:06 -0400","committer_email":"vbatts@hashbangbash.com","committer_name":"Vincent Batts","encoding":"","parent":"03bda4bcb2e741bc3e540ac171ba229bcfb47b9c","refs":"","sanitized_subject_line":"git-add-verbose-output-of-the-commands-run","signer":"","signer_key":"","subject":"git: add verbose output of the commands run","tree":"8a81024ef0d4e93d5852180f3c3f9ce10ae09cdb","verification_flag":"N"},{"abbreviated_commit":"03bda4b","abbreviated_parent":"c10ba9c","abbreviated_tree":"e41fbcb","author_date":"Mon, 5 Oct 2015 18:29:24 -0400","author_email":"vbatts@hashbangbash.com","author_name":"Vincent Batts","body":"Signed-off-by: Vincent Batts \u003cvbatts@hashbangbash.com\u003e","commit":"03bda4bcb2e741bc3e540ac171ba229bcfb47b9c","commit_notes":"","committer_date":"Mon, 5 Oct 2015 18:49:02 -0400","committer_email":"vbatts@hashbangbash.com","committer_name":"Vincent Batts","encoding":"","parent":"c10ba9c097ba2d5e0d5e834ae43252276a177e94","refs":"","sanitized_subject_line":"main-add-filtering-of-rules-to-run","signer":"","signer_key":"","subject":"main: add filtering of rules to run","tree":"e41fbcb527138c2cf49ee05d8adc55ba5d4d22f6","verification_flag":"N"},{"abbreviated_commit":"c10ba9c","abbreviated_parent":"","abbreviated_tree":"06f0e7a","author_date":"Mon, 5 Oct 2015 16:16:52 -0400","author_email":"vbatts@hashbangbash.com","author_name":"Vincent Batts","body":"Signed-off-by: Vincent Batts \u003cvbatts@hashbangbash.com\u003e","commit":"c10ba9c097ba2d5e0d5e834ae43252276a177e94","commit_notes":"","committer_date":"Mon, 5 Oct 2015 18:48:23 -0400","committer_email":"vbatts@hashbangbash.com","committer_name":"Vincent Batts","encoding":"","parent":"","refs":"","sanitized_subject_line":"Initial-commit","signer":"","signer_key":"","subject":"Initial commit","tree":"06f0e7a5b91783b052759a91c25fab7a22ce3ab4","verification_flag":"N"}]
\ No newline at end of file