From e366fe8103bf0085acf6132d1826945874b337a7 Mon Sep 17 00:00:00 2001
From: Paul Jolly <paul@myitcv.io>
Date: Sun, 18 Feb 2024 14:33:24 +0000
Subject: [PATCH] preprocessor: support hidden uploads

This allows guides which only choose to present select files (as opposed
to a full tutorial from start to end) can still be validated as working,
by uploading files which the user does not see. (The files themselves
are not hidden, just the upload block itself is not rendered in the Hugo
output).

Preprocessor-No-Write-Cache: true
Signed-off-by: Paul Jolly <paul@myitcv.io>
Change-Id: Ia7289d0fc730c744375c23a4136e57493baa1fcb
Dispatch-Trailer: {"type":"trybot","CL":1177013,"patchset":3,"ref":"refs/changes/13/1177013/3","targetBranch":"alpha"}
---
 internal/cmd/preprocessor/cmd/parse.go            |  8 ++++++--
 internal/cmd/preprocessor/cmd/rootfile.go         |  1 +
 .../cmd/testdata/execute_multistagescript.txtar   | 15 ++++++++++++++-
 internal/cmd/preprocessor/cmd/upload_node.go      | 13 ++++++++++++-
 4 files changed, 33 insertions(+), 4 deletions(-)

diff --git a/internal/cmd/preprocessor/cmd/parse.go b/internal/cmd/preprocessor/cmd/parse.go
index c71804e9b..bf1c968c2 100644
--- a/internal/cmd/preprocessor/cmd/parse.go
+++ b/internal/cmd/preprocessor/cmd/parse.go
@@ -216,12 +216,16 @@ func (rf *rootFile) parse_WithNode(n *parse.WithNode) (node, error) {
 		// Increment first because we are numbering from 1
 		rf.stepNumber++
 		return rf.parse_stepNode(n, rf.stepNumber)
-	case fnUpload:
+	case fnUpload, fnHiddenUpload:
+		hidden := fn.Ident == fnHiddenUpload
 		t, err := rf.parse_txtarNode(n, fn.Ident, c.Args[1:])
 		if err != nil {
 			return nil, err
 		}
-		return &uploadNode{txtarNode: t}, nil
+		return &uploadNode{
+			txtarNode: t,
+			hidden:    hidden,
+		}, nil
 	case fnScript, fnHiddenScript:
 		hidden := fn.Ident == fnHiddenScript
 		t, err := rf.parse_txtarNode(n, fn.Ident, c.Args[1:])
diff --git a/internal/cmd/preprocessor/cmd/rootfile.go b/internal/cmd/preprocessor/cmd/rootfile.go
index 1b885856a..36a69f5ad 100644
--- a/internal/cmd/preprocessor/cmd/rootfile.go
+++ b/internal/cmd/preprocessor/cmd/rootfile.go
@@ -47,6 +47,7 @@ var (
 		fnCode:         true,
 		fnStep:         true,
 		fnUpload:       true,
+		fnHiddenUpload: true,
 		fnScript:       true,
 		fnHiddenScript: true,
 		"reference":    true,
diff --git a/internal/cmd/preprocessor/cmd/testdata/execute_multistagescript.txtar b/internal/cmd/preprocessor/cmd/testdata/execute_multistagescript.txtar
index 6db40fade..4882b353a 100644
--- a/internal/cmd/preprocessor/cmd/testdata/execute_multistagescript.txtar
+++ b/internal/cmd/preprocessor/cmd/testdata/execute_multistagescript.txtar
@@ -71,6 +71,12 @@ content: dir: page: {
 >title: JSON Superset
 >---
 >{{{with step}}}
+>
+>{{{with _upload "en" "hidden file"}}}
+>-- hidden.txt --
+>Secret message
+>{{{end}}}
+>
 >{{{with upload "en" "upload-some-cue"}}}
 >#codetab(in.cue) linenos="table"
 >-- in.cue --
@@ -121,6 +127,12 @@ content: dir: page: {
 >title: JSON Superset
 >---
 >{{{with step}}}
+>
+>{{{with _upload "en" "hidden file"}}}
+>-- hidden.txt --
+>Secret message
+>{{{end}}}
+>
 >{{{with upload "en" "upload-some-cue"}}}
 >#codetab(in.cue) linenos="table"
 >-- in.cue --
@@ -233,12 +245,13 @@ package site
 			page: {
 				cache: {
 					upload: {
+						"hidden file":      "4YPap9a6NsyJd6KTPyStBOl3FcJsYecsnKRpcixFfrY="
 						"upload-some-cue":  "mk/eGLXQi8f2VHFEAJ+OVwSB0C/zK9S8nvtSvKYNyVo="
 						"upload-some-json": "aOFY1SpvCxmIPWnBoZDfTCvL90OvzbTTD3gqObCa75w="
 						"in-subdir":        "zLF5NHI4Y1eaRJ7n4t6bN//ptgOj2snRyP3DNUSUZrw="
 					}
 					multi_step: {
-						"L4H91P78HIDIAEMM7U0CA93FTU24VD5B7K7E0BRUPJPUM8AV9RV0====": [{
+						"3UA3H59NARBLHE6A3D5HAM0BD8RJH3L54NR16HOO9JUDU58IM1HG====": [{
 							doc: """
 									# script doc comment
 									#scripttag
diff --git a/internal/cmd/preprocessor/cmd/upload_node.go b/internal/cmd/preprocessor/cmd/upload_node.go
index ffc508d08..87e5de7aa 100644
--- a/internal/cmd/preprocessor/cmd/upload_node.go
+++ b/internal/cmd/preprocessor/cmd/upload_node.go
@@ -18,10 +18,17 @@ import (
 	"bytes"
 )
 
-const fnUpload = "upload"
+const (
+	fnUpload       = "upload"
+	fnHiddenUpload = "_upload"
+)
 
 type uploadNode struct {
 	txtarNode
+
+	// hidden is set to indicate the script exists for side effects
+	// only and will not be rendered
+	hidden bool
 }
 
 var _ validatingNode = (*uploadNode)(nil)
@@ -30,6 +37,10 @@ func (u *uploadNode) nodeType() string {
 	return "upload"
 }
 
+func (u *uploadNode) isHidden() bool {
+	return u.hidden
+}
+
 func (u *uploadNode) validate() {
 	if l := len(u.analysis.fileNames); l != 1 {
 		u.errorf("%v: upload nodes can only contain a single file; saw %d", u, l)