httpcaddyfile: Ensure handle_path is sorted equally to handle (#3676)

* httpcaddyfile: Ensure handle_path is sorted as equal to handle

* httpcaddyfile: Make mutual exclusivity grouping deterministic (I hope)

* httpcaddyfile: Add comment linking to the issue being fixed

* httpcaddyfile: Typo fix, comment clarity

Co-authored-by: Matt Holt <mholt@users.noreply.github.com>

* Update caddyconfig/httpcaddyfile/httptype.go

Co-authored-by: Matt Holt <mholt@users.noreply.github.com>

caddyconfig/httpcaddyfile/httptype.go

@@ -172,6 +172,15 @@ func (st ServerType) Setup(inputServerBlocks []caddyfile.ServerBlock,
 			if err != nil {
 				return nil, warnings, fmt.Errorf("parsing caddyfile tokens for '%s': %v", dir, err)
 			}
+
+			// As a special case, we want "handle_path" to be sorted
+			// at the same level as "handle", so we force them to use
+			// the same directive name after their parsing is complete.
+			// See https://github.com/caddyserver/caddy/issues/3675#issuecomment-678042377
+			if dir == "handle_path" {
+				dir = "handle"
+			}
+
 			for _, result := range results {
 				result.directive = dir
 				sb.pile[result.Class] = append(sb.pile[result.Class], result)
@@ -854,7 +863,18 @@ func buildSubroute(routes []ConfigValue, groupCounter counter) (*caddyhttp.Subro
 		// root directives would overwrite previously-matched ones; they should not cascade
 		"root": {},
 	}
-	for meDir, info := range mutuallyExclusiveDirs {
+
+	// we need to deterministically loop over each of these directives
+	// in order to keep the group numbers consistent
+	keys := make([]string, 0, len(mutuallyExclusiveDirs))
+	for k := range mutuallyExclusiveDirs {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+
+	for _, meDir := range keys {
+		info := mutuallyExclusiveDirs[meDir]
+
 		// see how many instances of the directive there are
 		for _, r := range routes {
 			if r.directive == meDir {

caddytest/integration/caddyfile_adapt/handle_path_sorting.txt

@@ -0,0 +1,105 @@
+:80 {
+	handle /api/* {
+		respond "api"
+	}
+
+	handle_path /static/* {
+		respond "static"
+	}
+
+	handle {
+		respond "handle"
+	}
+}
+----------
+{
+	"apps": {
+		"http": {
+			"servers": {
+				"srv0": {
+					"listen": [
+						":80"
+					],
+					"routes": [
+						{
+							"group": "group3",
+							"match": [
+								{
+									"path": [
+										"/static/*"
+									]
+								}
+							],
+							"handle": [
+								{
+									"handler": "subroute",
+									"routes": [
+										{
+											"handle": [
+												{
+													"handler": "rewrite",
+													"strip_path_prefix": "/static"
+												}
+											]
+										},
+										{
+											"handle": [
+												{
+													"body": "static",
+													"handler": "static_response"
+												}
+											]
+										}
+									]
+								}
+							]
+						},
+						{
+							"group": "group3",
+							"match": [
+								{
+									"path": [
+										"/api/*"
+									]
+								}
+							],
+							"handle": [
+								{
+									"handler": "subroute",
+									"routes": [
+										{
+											"handle": [
+												{
+													"body": "api",
+													"handler": "static_response"
+												}
+											]
+										}
+									]
+								}
+							]
+						},
+						{
+							"group": "group3",
+							"handle": [
+								{
+									"handler": "subroute",
+									"routes": [
+										{
+											"handle": [
+												{
+													"body": "handle",
+													"handler": "static_response"
+												}
+											]
+										}
+									]
+								}
+							]
+						}
+					]
+				}
+			}
+		}
+	}
+}