Add some test cases to cover main

These don't include any asserts, but they do check panics

main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"fmt"
 	"log"
 	"time"
 )
@@ -12,11 +13,14 @@ func checkMonitors(config *Config) {
 
 			// Should probably consider refactoring everything below here
 			if alertNotice != nil {
-				log.Printf("DEBUG: Recieved an alert notice: %v", alertNotice)
+				log.Printf("DEBUG: Recieved an alert notice from %s", alertNotice.MonitorName)
 				alertNames := monitor.GetAlertNames(alertNotice.IsUp)
 				if alertNames == nil {
 					// TODO: Should this be a panic? Should this be validated against? Probably
-					log.Printf("WARNING: Found alert, but no alert mechanisms exist: %v", alertNotice)
+					log.Printf(
+						"WARNING: Recieved alert, but no alert mechanisms exist. MonitorName=%s IsUp=%t",
+						alertNotice.MonitorName, alertNotice.IsUp,
+					)
 				}
 				for _, alertName := range alertNames {
 					if alert, ok := config.Alerts[alertName]; ok {
@@ -29,12 +33,12 @@ func checkMonitors(config *Config) {
 								output,
 							)
 							// TODO: Maybe return this error instead of panicking here
-							log.Fatalf(
+							panic(fmt.Errorf(
 								"ERROR: Unsuccessfully triggered alert '%s'. "+
 									"Crashing to avoid false negatives: %v",
 								alert.Name,
 								err,
-							)
+							))
 						}
 					} else {
 						// TODO: Maybe panic here. Also, probably validate up front

main_test.go

@@ -0,0 +1,122 @@
+package main
+
+import "testing"
+
+func TestCheckMonitors(t *testing.T) {
+	cases := []struct {
+		config      Config
+		expectPanic bool
+		name        string
+	}{
+		{
+			config:      Config{},
+			expectPanic: false,
+			name:        "Empty",
+		},
+		{
+			config: Config{
+				Monitors: []*Monitor{
+					&Monitor{
+						Name:    "Success",
+						Command: []string{"true"},
+					},
+				},
+			},
+			expectPanic: false,
+			name:        "Monitor success, no alerts",
+		},
+		{
+			config: Config{
+				Monitors: []*Monitor{
+					&Monitor{
+						Name:       "Failure",
+						Command:    []string{"false"},
+						AlertAfter: 1,
+					},
+					&Monitor{
+						Name:       "Failure",
+						Command:    []string{"false"},
+						AlertDown:  []string{"unknown"},
+						AlertAfter: 1,
+					},
+				},
+			},
+			expectPanic: false,
+			name:        "Monitor failure, no and unknown alerts",
+		},
+		{
+			config: Config{
+				Monitors: []*Monitor{
+					&Monitor{
+						Name:       "Success",
+						Command:    []string{"ls"},
+						alertCount: 1,
+					},
+					&Monitor{
+						Name:       "Success",
+						Command:    []string{"true"},
+						AlertUp:    []string{"unknown"},
+						alertCount: 1,
+					},
+				},
+			},
+			expectPanic: false,
+			name:        "Monitor recovery, no alerts",
+		},
+		{
+			config: Config{
+				Monitors: []*Monitor{
+					&Monitor{
+						Name:       "Failure",
+						Command:    []string{"false"},
+						AlertDown:  []string{"good"},
+						AlertAfter: 1,
+					},
+				},
+				Alerts: map[string]*Alert{
+					"good": &Alert{
+						Command: []string{"true"},
+					},
+				},
+			},
+			expectPanic: false,
+			name:        "Monitor failure, successful alert",
+		},
+		{
+			config: Config{
+				Monitors: []*Monitor{
+					&Monitor{
+						Name:       "Failure",
+						Command:    []string{"false"},
+						AlertDown:  []string{"bad"},
+						AlertAfter: 1,
+					},
+				},
+				Alerts: map[string]*Alert{
+					"bad": &Alert{
+						Name:    "bad",
+						Command: []string{"false"},
+					},
+				},
+			},
+			expectPanic: true,
+			name:        "Monitor failure, bad alert",
+		},
+	}
+
+	for _, c := range cases {
+		// Create new function so that deferred recovery can run at end of each test case
+		func() {
+			// Set up recover to catch panic
+			defer func() {
+				if r := recover(); r == nil {
+					if c.expectPanic {
+						t.Errorf("checkMonitors(%s): Expected panic, the code did not panic", c.name)
+					}
+				}
+			}()
+			c.config.Init()
+			checkMonitors(&c.config)
+		}()
+	}
+}