feat(core): allow defining target with only dependsOn (#26545)

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## Current Behavior
You must specify either `executor` or `command`, otherwise the target is
removed.

## Expected Behavior
If a target specifies `dependsOn` it is not removed.

## Related Issue(s)
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merged. -->

Fixes #

packages/nx/src/project-graph/utils/normalize-project-nodes.ts

@@ -43,7 +43,7 @@ export async function normalizeProjectNodes(
       partialProjectGraphNodes
     );
 
-    p.targets = normalizeProjectTargets(p, key);
+    p.targets ??= {};
 
     // TODO: remove in v16
     const projectType =
@@ -80,25 +80,6 @@ export async function normalizeProjectNodes(
   });
 }
 
-/**
- * Apply target defaults and normalization
- */
-export function normalizeProjectTargets(
-  project: ProjectConfiguration,
-  projectName: string
-): Record<string, TargetConfiguration> {
-  // Any node on the graph will have a targets object, it just may be empty
-  const targets = project.targets ?? {};
-
-  for (const target in targets) {
-    if (!targets[target].command && !targets[target].executor) {
-      delete targets[target];
-      continue;
-    }
-  }
-  return targets;
-}
-
 export function normalizeImplicitDependencies(
   source: string,
   implicitDependencies: ProjectConfiguration['implicitDependencies'],

packages/nx/src/project-graph/utils/project-configuration-utils.ts

@@ -641,10 +641,21 @@ function validateAndNormalizeProjectRootMap(
       );
 
       if (
+        // If the target has no executor or command, it doesn't do anything
         !project.targets[targetName].executor &&
         !project.targets[targetName].command
       ) {
-        delete project.targets[targetName];
+        // But it may have dependencies that do something
+        if (
+          project.targets[targetName].dependsOn &&
+          project.targets[targetName].dependsOn.length > 0
+        ) {
+          project.targets[targetName].executor = 'nx:noop';
+        } else {
+          // If it does nothing, and has no depenencies,
+          // we can remove it.
+          delete project.targets[targetName];
+        }
       }
     }
   }