break a chain of post-processors when one is skipped & make `-only`

"blind" to post-processors

* to avoid trouble
* other arrays of post processors might still be there !
* add docs
* update tests

command/build_test.go

@@ -27,12 +27,13 @@ func TestBuildOnlyFileCommaFlags(t *testing.T) {
 		fatalCommand(t, c.Meta)
 	}
 
-	if !fileExists("chocolate.txt") {
-		t.Error("Expected to find chocolate.txt")
+	for _, f := range []string{"chocolate.txt", "vanilla.txt",
+		"apple.txt", "peach.txt", "pear.txt"} {
+		if !fileExists(f) {
+			t.Errorf("Expected to find %s", f)
 		}
-	if !fileExists("vanilla.txt") {
-		t.Error("Expected to find vanilla.txt")
 	}
+
 	if fileExists("cherry.txt") {
 		t.Error("Expected NOT to find cherry.txt")
 	}
@@ -57,14 +58,10 @@ func TestBuildStdin(t *testing.T) {
 		fatalCommand(t, c.Meta)
 	}
 
-	if !fileExists("chocolate.txt") {
-		t.Error("Expected to find chocolate.txt")
+	for _, f := range []string{"vanilla.txt", "cherry.txt", "chocolate.txt"} {
+		if !fileExists(f) {
+			t.Errorf("Expected to find %s", f)
 		}
-	if !fileExists("vanilla.txt") {
-		t.Error("Expected to find vanilla.txt")
-	}
-	if !fileExists("cherry.txt") {
-		t.Error("Expected to find cherry.txt")
 	}
 }
 
@@ -76,7 +73,9 @@ func TestBuildOnlyFileMultipleFlags(t *testing.T) {
 	args := []string{
 		"-only=chocolate",
 		"-only=cherry",
-		"-only=apple",
+		"-only=apple", // ignored
+		"-only=peach", // ignored
+		"-only=pear",  // ignored
 		filepath.Join(testFixture("build-only"), "template.json"),
 	}
 
@@ -86,17 +85,16 @@ func TestBuildOnlyFileMultipleFlags(t *testing.T) {
 		fatalCommand(t, c.Meta)
 	}
 
-	if !fileExists("chocolate.txt") {
-		t.Error("Expected to find chocolate.txt")
+	for _, f := range []string{"vanilla.txt"} {
+		if fileExists(f) {
+			t.Errorf("Expected NOT to find %s", f)
 		}
-	if fileExists("vanilla.txt") {
-		t.Error("Expected NOT to find vanilla.txt")
 	}
-	if !fileExists("cherry.txt") {
-		t.Error("Expected to find cherry.txt")
+	for _, f := range []string{"chocolate.txt", "cherry.txt",
+		"apple.txt", "peach.txt", "pear.txt"} {
+		if !fileExists(f) {
+			t.Errorf("Expected to find %s", f)
 		}
-	if !fileExists("apple.txt") {
-		t.Error("Expected to find apple.txt")
 	}
 }
 
@@ -116,12 +114,12 @@ func TestBuildExceptFileCommaFlags(t *testing.T) {
 		fatalCommand(t, c.Meta)
 	}
 
-	for _, f := range []string{"chocolate.txt", "apple.txt"} {
+	for _, f := range []string{"chocolate.txt", "apple.txt", "peach.txt"} {
 		if fileExists(f) {
 			t.Errorf("Expected NOT to find %s", f)
 		}
 	}
-	for _, f := range []string{"vanilla.txt", "cherry.txt", "peach.txt"} {
+	for _, f := range []string{"vanilla.txt", "cherry.txt", "pear.txt"} {
 		if !fileExists(f) {
 			t.Errorf("Expected to find %s", f)
 		}
@@ -170,4 +168,5 @@ func cleanup() {
 	os.RemoveAll("cherry.txt")
 	os.RemoveAll("apple.txt")
 	os.RemoveAll("peach.txt")
+	os.RemoveAll("pear.txt")
 }

command/test-fixtures/build-only/template.json

@@ -20,6 +20,7 @@
         }
     ],
     "post-processors": [
+        [
             {
                 "name": "apple",
                 "type": "shell-local",
@@ -30,5 +31,13 @@
                 "type": "shell-local",
                 "inline": [ "touch peach.txt" ]
             }
+        ],
+        [
+            {
+                "name": "pear",
+                "type": "shell-local",
+                "inline": [ "touch pear.txt" ]
+            }
+        ]
     ]
 }

packer/core.go

@@ -182,12 +182,11 @@ func (c *Core) Build(n string) (Build, error) {
 		for _, rawP := range rawPs {
 			// If we skip, ignore
 			rawP.OnlyExcept.Except = append(rawP.OnlyExcept.Except, c.except...)
-			rawP.OnlyExcept.Only = append(rawP.OnlyExcept.Only, c.only...)
 			if rawP.OnlyExcept.Skip(rawName) {
 				continue
 			}
 			if rawP.OnlyExcept.Skip(rawP.Name) {
-				continue
+				break
 			}
 
 			// Get the post-processor

website/source/docs/commands/build.html.md

@@ -26,10 +26,12 @@ artifacts that are created will be outputted at the end of the build.
     will stop between each step, waiting for keyboard input before continuing.
     This will allow the user to inspect state and so on.
 
--   `-except=foo,bar,baz` - Run all the builds and post-processors except
-    those with the given comma-separated names. Build and post-processor names
-    by default are their type, unless a specific `name` attribute is specified
-    within the configuration.
+-   `-except=foo,bar,baz` - Run all the builds and post-processors except those
+    with the given comma-separated names. Build and post-processor names by
+    default are their type, unless a specific `name` attribute is specified
+    within the configuration. Any post-processor following a skipped
+    post-processor will not run. Because post-processors can be nested in
+    arrays a differ post-processor chain can still run.
 
 -   `-force` - Forces a builder to run when artifacts from a previous build
     prevent a build from running. The exact behavior of a forced build is left
@@ -44,10 +46,10 @@ artifacts that are created will be outputted at the end of the build.
     presents a prompt and waits for you to decide to clean up, abort, or retry
     the failed step.
 
--   `-only=foo,bar,baz` - Only run the builds and post-processors with the
-    given comma-separated names. Build and post-processor names by default are
-    their type, unless a specific `name` attribute is specified within the
-    configuration.
+-   `-only=foo,bar,baz` - Only run the builds with the given comma-separated
+    names. Build names by default are their type, unless a specific `name`
+    attribute is specified within the configuration. `-only` does not apply to
+    post-processors.
 
 -   `-parallel=false` - Disable parallelization of multiple builders (on by
     default).

website/source/docs/templates/provisioners.html.md

@@ -77,10 +77,11 @@ effectively the same:
 }
 ```
 
-The values within `only` or `except` can be *build or post-processor names*,
-not builder types. If you recall, build and post-processor names by default are
-just their builder type, but if you specify a custom `name` parameter, then you
-should use that as the value instead of the type.
+The values within `only` or `except` are *build names*, not builder types. If
+you recall, build names by default are just their builder type, but if you
+specify a custom `name` parameter, then you should use that as the value
+instead of the type.
+Values within `except` could also be a *post-processor* name.
 
 ## Build-Specific Overrides