fix(custom-fields): preserve JSON objects/arrays in --custom values

pkg/jira/create.go

@@ -240,6 +240,10 @@ func constructCustomFields(fields map[string]string, configuredFields []IssueTyp
 			if identifier != strings.ToLower(key) {
 				continue
 			}
+			if parsed, ok := parseCustomFieldJSONContainer(val); ok {
+				data.Fields.M.customFields[configured.Key] = parsed
+				continue
+			}
 
 			switch configured.Schema.DataType {
 			case customFieldFormatOption:

pkg/jira/customfield.go

@@ -19,6 +19,10 @@ type customFieldTypeStringSet struct {
 	Set string `json:"set"`
 }
 
+type customFieldTypeAnySet struct {
+	Set any `json:"set"`
+}
+
 type customFieldTypeOption struct {
 	Value string `json:"value"`
 }

pkg/jira/customfield_json_test.go

@@ -0,0 +1,80 @@
+package jira
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestConstructCustomFieldsParsesNestedJSONObjectForCreate(t *testing.T) {
+	req := CreateRequest{
+		Project:   "TEST",
+		IssueType: "Task",
+		Summary:   "Test issue",
+		CustomFields: map[string]string{
+			"reviewers": `{"accountId":"abc","profile":{"team":{"id":"42"}}}`,
+		},
+	}
+	req.WithCustomFields([]IssueTypeField{
+		{
+			Name: "reviewers",
+			Key:  "customfield_10042",
+			Schema: struct {
+				DataType string `json:"type"`
+				Items    string `json:"items,omitempty"`
+			}{
+				DataType: "user",
+			},
+		},
+	})
+
+	body, err := json.Marshal((&Client{}).getRequestData(&req))
+	assert.NoError(t, err)
+	assert.JSONEq(t, `{
+		"update": {},
+		"fields": {
+			"project": {"key": "TEST"},
+			"issuetype": {"name": "Task"},
+			"summary": "Test issue",
+			"customfield_10042": {
+				"accountId": "abc",
+				"profile": {"team": {"id": "42"}}
+			}
+		}
+	}`, string(body))
+}
+
+func TestConstructCustomFieldsParsesNestedJSONObjectForEdit(t *testing.T) {
+	req := EditRequest{
+		CustomFields: map[string]string{
+			"reviewers": `{"accountId":"abc","profile":{"team":{"members":[{"id":"1"},{"id":"2"}]}}}`,
+		},
+	}
+	req.WithCustomFields([]IssueTypeField{
+		{
+			Name: "reviewers",
+			Key:  "customfield_10042",
+			Schema: struct {
+				DataType string `json:"type"`
+				Items    string `json:"items,omitempty"`
+			}{
+				DataType: "user",
+			},
+		},
+	})
+
+	body, err := json.Marshal(getRequestDataForEdit(&req))
+	assert.NoError(t, err)
+	assert.JSONEq(t, `{
+		"update": {
+			"customfield_10042": [{
+				"set": {
+					"accountId": "abc",
+					"profile": {"team": {"members": [{"id":"1"},{"id":"2"}]}}
+				}
+			}]
+		},
+		"fields": {"parent": {}}
+	}`, string(body))
+}

pkg/jira/customfield_parser.go

@@ -0,0 +1,24 @@
+package jira
+
+import (
+	"encoding/json"
+	"strings"
+)
+
+func parseCustomFieldJSONContainer(v string) (any, bool) {
+	trimmed := strings.TrimSpace(v)
+	if trimmed == "" {
+		return nil, false
+	}
+
+	if !strings.HasPrefix(trimmed, "{") && !strings.HasPrefix(trimmed, "[") {
+		return nil, false
+	}
+
+	var out any
+	if err := json.Unmarshal([]byte(trimmed), &out); err != nil {
+		return nil, false
+	}
+
+	return out, true
+}

pkg/jira/edit.go

@@ -371,6 +371,10 @@ func constructCustomFieldsForEdit(fields map[string]string, configuredFields []I
 			if identifier != strings.ToLower(key) {
 				continue
 			}
+			if parsed, ok := parseCustomFieldJSONContainer(val); ok {
+				data.Update.M.customFields[configured.Key] = []customFieldTypeAnySet{{Set: parsed}}
+				continue
+			}
 
 			switch configured.Schema.DataType {
 			case customFieldFormatOption: