parse messages

event_proxy/main_test.go

@@ -0,0 +1,116 @@
+package main
+
+import (
+	"testing"
+)
+
+func TestParseMsg(t *testing.T) {
+	tests := []struct {
+		name      string
+		input     string
+		wantID    int
+		wantData  []string
+		wantError bool
+	}{
+		{
+			name:      "valid message with single data element",
+			input:     "M01,25.5",
+			wantID:    1,
+			wantData:  []string{"25.5"},
+			wantError: false,
+		},
+		{
+			name:      "valid message with multiple data elements",
+			input:     "M02,25.5,60,1013",
+			wantID:    2,
+			wantData:  []string{"25.5", "60", "1013"},
+			wantError: false,
+		},
+		{
+			name:      "valid message with ID only",
+			input:     "M0",
+			wantID:    0,
+			wantData:  []string{},
+			wantError: false,
+		},
+		{
+			name:      "invalid message with non-numeric ID",
+			input:     "Mabc,data",
+			wantID:    0,
+			wantData:  nil,
+			wantError: true,
+		},
+		{
+			name:      "invalid message with missing M prefix",
+			input:     "1,data",
+			wantID:    0,
+			wantData:  nil,
+			wantError: true,
+		},
+		{
+			name:      "invalid message with empty string",
+			input:     "",
+			wantID:    0,
+			wantData:  nil,
+			wantError: true,
+		},
+		{
+			name:      "valid message with empty data elements",
+			input:     "M5,,data,,",
+			wantID:    5,
+			wantData:  []string{"", "data", "", ""},
+			wantError: false,
+		},
+		{
+			name:      "valid message with special characters in data",
+			input:     "M10,key=value!@#$",
+			wantID:    10,
+			wantData:  []string{"key=value!@#$"},
+			wantError: false,
+		},
+		{
+			name:      "newlines and whitespace are stripped from data",
+			input:     "M1,1.0,1.1,1.2\n",
+			wantID:    1,
+			wantData:  []string{"1.0", "1.1", "1.2"},
+			wantError: false,
+		},
+		{
+			name:      "leading and trailing whitespace stripped",
+			input:     "M5, data1 , data2 \t, data3\r\n",
+			wantID:    5,
+			wantData:  []string{"data1", "data2", "data3"},
+			wantError: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := ParseMsg(tt.input)
+
+			if (err != nil) != tt.wantError {
+				t.Errorf("ParseMsg() error = %v, wantError %v", err, tt.wantError)
+				return
+			}
+
+			if tt.wantError {
+				return
+			}
+
+			if got.ID != tt.wantID {
+				t.Errorf("ParseMsg() ID = %d, want %d", got.ID, tt.wantID)
+			}
+
+			if len(got.Data) != len(tt.wantData) {
+				t.Errorf("ParseMsg() data length = %d, want %d", len(got.Data), len(tt.wantData))
+				return
+			}
+
+			for i, val := range got.Data {
+				if val != tt.wantData[i] {
+					t.Errorf("ParseMsg() data[%d] = %q, want %q", i, val, tt.wantData[i])
+				}
+			}
+		})
+	}
+}