Improve clarity a bit more.

Author: rictic

src/execution/standard.ts

@@ -410,7 +410,7 @@ export class StandardScriptExecution extends BaseExecutionWithCommand<StandardSc
         type: 'info',
         detail: 'running',
         notFreshReason,
-        executionRequestedReason: executionRequestedReason,
+        executionRequestedReason,
       });
 
       const child = new ScriptChildProcess(

src/fingerprint.ts

@@ -295,19 +295,6 @@ export class Fingerprint {
     return this.string === other.string;
   }
 
-  requiresRebuild(previous: Fingerprint | undefined): boolean {
-    // If we're not fully tracked, we always need to rebuild.
-    if (!this.data.fullyTracked) {
-      return true;
-    }
-    // If we don't have a previous fingerprint, we need to rebuild.
-    if (previous === undefined) {
-      return true;
-    }
-    // Otherwise, we need to rebuild if the fingerprint changed.
-    return !this.equal(previous);
-  }
-
   difference(previous: Fingerprint): FingerprintDifference | undefined {
     // Do a string comparison first, because it's much faster than
     // checking field by field;

src/logging/default-logger.ts

@@ -7,7 +7,12 @@
 import * as pathlib from 'path';
 import {unreachable} from '../util/unreachable.js';
 
-import type {Event} from '../event.js';
+import type {
+  Event,
+  FingerprintDifference,
+  NeedsToRunReason,
+  ServiceStoppedReason,
+} from '../event.js';
 import type {Logger} from './logger.js';
 import {
   stringToScriptReference,
@@ -315,138 +320,7 @@ export class DefaultLogger implements Logger {
             break;
           }
           case 'service-stopped': {
-            let reason: string;
-            switch (event.reason.name) {
-              default: {
-                const never: never = event.reason;
-                throw new Error(
-                  `Unknown service stop reason: ${inspect(never)}`,
-                );
-              }
-              case 'all consumers of the service are done':
-              case 'the depgraph changed, service is no longer needed':
-              case 'the run was aborted':
-              case 'unknown':
-                reason = event.reason.name;
-                break;
-              case 'restart': {
-                const restartReason = event.reason;
-                switch (restartReason.reason.name) {
-                  default: {
-                    const never: never = restartReason.reason;
-                    throw new Error(
-                      `Unknown restart reason: ${inspect(never)}`,
-                    );
-                  }
-                  case 'not-fully-tracked': {
-                    const notFullyTrackedReason = restartReason.reason.reason;
-                    switch (notFullyTrackedReason.name) {
-                      default: {
-                        const never: never = notFullyTrackedReason;
-                        throw new Error(
-                          `Unknown not-fully-tracked reason: ${inspect(never)}`,
-                        );
-                      }
-                      case 'dependency not fully tracked': {
-                        reason = `the service depends on ${labelForScript(
-                          this.rootPackageDir,
-                          stringToScriptReference(
-                            notFullyTrackedReason.dependency,
-                          ),
-                        )}`;
-                        break;
-                      }
-                      case 'no files field': {
-                        throw new Error(
-                          'Internal error: a service is tracked even without a files field',
-                        );
-                      }
-                      case 'no output field': {
-                        throw new Error(
-                          'Internal error: a service never has output',
-                        );
-                      }
-                    }
-                    break;
-                  }
-                  case 'no-previous-fingerprint': {
-                    throw new Error(
-                      'Internal error: could not find a previous fingerprint, so we restarted the server?',
-                    );
-                  }
-                  case 'fingerprints-differed': {
-                    const difference = restartReason.reason.difference;
-                    switch (difference.name) {
-                      default: {
-                        const never: never = difference;
-                        throw new Error(
-                          `Unknown not-fully-tracked reason: ${inspect(never)}`,
-                        );
-                      }
-                      case 'config': {
-                        reason = `config field ${
-                          difference.field
-                        } changed from ${inspect(
-                          difference.previous,
-                        )} to ${inspect(difference.current)}`;
-                        break;
-                      }
-                      case 'environment': {
-                        reason = `the ${
-                          difference.field
-                        } of the environment changed from ${inspect(
-                          difference.previous,
-                        )} to ${inspect(difference.current)}`;
-                        break;
-                      }
-                      case 'dependency added': {
-                        reason = `a dependency was added: [${labelForScript(
-                          this.rootPackageDir,
-                          stringToScriptReference(difference.script),
-                        )}]`;
-                        break;
-                      }
-                      case 'dependency removed': {
-                        reason = `a dependency was removed: [${labelForScript(
-                          this.rootPackageDir,
-                          stringToScriptReference(difference.script),
-                        )}]`;
-                        break;
-                      }
-                      case 'dependency changed': {
-                        reason = `a dependency changed: [${labelForScript(
-                          this.rootPackageDir,
-                          stringToScriptReference(difference.script),
-                        )}]`;
-                        break;
-                      }
-                      case 'file added': {
-                        reason = `a file was added: ${pathlib.relative(
-                          this.rootPackageDir,
-                          difference.path,
-                        )}`;
-                        break;
-                      }
-                      case 'file removed': {
-                        reason = `a file was removed: ${pathlib.relative(
-                          this.rootPackageDir,
-                          difference.path,
-                        )}`;
-                        break;
-                      }
-                      case 'file changed': {
-                        reason = `a file was changed: ${pathlib.relative(
-                          this.rootPackageDir,
-                          difference.path,
-                        )}`;
-                        break;
-                      }
-                    }
-                  }
-                }
-                break;
-              }
-            }
+            const reason = this.#explainServiceStopped(event.reason);
             console.log(`⬇️${prefix} Service stopped because ${reason}`);
             if (event.failure !== undefined) {
               // Use console.group to indent
@@ -466,6 +340,124 @@ export class DefaultLogger implements Logger {
     }
   }
 
+  #explainServiceStopped(reason: ServiceStoppedReason): string {
+    switch (reason.name) {
+      default: {
+        const never: never = reason;
+        throw new Error(`Unknown service stop reason: ${inspect(never)}`);
+      }
+      case 'all consumers of the service are done':
+      case 'the depgraph changed, service is no longer needed':
+      case 'the run was aborted':
+      case 'unknown':
+        return reason.name;
+      case 'restart': {
+        return this.#explainServiceRestart(reason.reason);
+      }
+    }
+  }
+
+  #explainServiceRestart(reason: NeedsToRunReason): string {
+    switch (reason.name) {
+      default: {
+        const never: never = reason;
+        throw new Error(`Unknown restart reason: ${inspect(never)}`);
+      }
+      case 'not-fully-tracked': {
+        const notFullyTrackedReason = reason.reason;
+        switch (notFullyTrackedReason.name) {
+          default: {
+            const never: never = notFullyTrackedReason;
+            throw new Error(
+              `Unknown not-fully-tracked reason: ${inspect(never)}`,
+            );
+          }
+          case 'dependency not fully tracked': {
+            return `the service depends on [${labelForScript(
+              this.rootPackageDir,
+              stringToScriptReference(notFullyTrackedReason.dependency),
+            )}] which must always be run`;
+          }
+          case 'no files field': {
+            throw new Error(
+              'Internal error: a service is tracked even without a files field',
+            );
+          }
+          case 'no output field': {
+            throw new Error('Internal error: a service never has output');
+          }
+        }
+      }
+      case 'no-previous-fingerprint': {
+        throw new Error(
+          'Internal error: could not find a previous fingerprint, so we restarted the server?',
+        );
+      }
+      case 'fingerprints-differed': {
+        return this.#explainServiceFingerprintDifference(reason.difference);
+      }
+    }
+  }
+
+  #explainServiceFingerprintDifference(
+    difference: FingerprintDifference,
+  ): string {
+    switch (difference.name) {
+      default: {
+        const never: never = difference;
+        throw new Error(`Unknown not-fully-tracked reason: ${inspect(never)}`);
+      }
+      case 'config': {
+        return `config field ${difference.field} changed from ${inspect(
+          difference.previous,
+        )} to ${inspect(difference.current)}`;
+      }
+      case 'environment': {
+        return `the ${
+          difference.field
+        } of the environment changed from ${inspect(
+          difference.previous,
+        )} to ${inspect(difference.current)}`;
+      }
+      case 'dependency added': {
+        return `a dependency was added: [${labelForScript(
+          this.rootPackageDir,
+          stringToScriptReference(difference.script),
+        )}]`;
+      }
+      case 'dependency removed': {
+        return `a dependency was removed: [${labelForScript(
+          this.rootPackageDir,
+          stringToScriptReference(difference.script),
+        )}]`;
+      }
+      case 'dependency changed': {
+        return `a dependency changed: [${labelForScript(
+          this.rootPackageDir,
+          stringToScriptReference(difference.script),
+        )}]`;
+      }
+      case 'file added': {
+        return `a file was added: ${pathlib.relative(
+          this.rootPackageDir,
+          difference.path,
+        )}`;
+      }
+      case 'file removed': {
+        return `a file was removed: ${pathlib.relative(
+          this.rootPackageDir,
+          difference.path,
+        )}`;
+      }
+      case 'file changed': {
+        return `a file was changed: ${pathlib.relative(
+          this.rootPackageDir,
+          difference.path,
+        )}`;
+      }
+    }
+  }
+
   printMetrics(): void {
     // printMetrics() not used in default-logger.
   }