From 54032316f90672da1e86b1df878d59c865a8f756 Mon Sep 17 00:00:00 2001
From: CrazyMax <1951866+crazy-max@users.noreply.github.com>
Date: Tue, 28 Nov 2023 11:55:47 +0100
Subject: [PATCH] build: infer platform from first node if none set

Signed-off-by: CrazyMax <1951866+crazy-max@users.noreply.github.com>
---
 build/driver.go      | 35 +++++++++++++++++------------------
 build/driver_test.go |  4 ++--
 2 files changed, 19 insertions(+), 20 deletions(-)

diff --git a/build/driver.go b/build/driver.go
index 0096459e..ef0a4e1e 100644
--- a/build/driver.go
+++ b/build/driver.go
@@ -166,35 +166,34 @@ func (r *nodeResolver) resolve(ctx context.Context, ps []specs.Platform, pw prog
 
 	perfect := true
 	nodeIdxs := make([]int, 0)
-	if len(ps) == 0 {
-		idx := r.get(platforms.DefaultSpec(), matcher, additional)
+	for _, p := range ps {
+		idx := r.get(p, matcher, additional)
 		if idx == -1 {
 			idx = 0
 			perfect = false
 		}
 		nodeIdxs = append(nodeIdxs, idx)
-	} else {
-		for _, p := range ps {
-			idx := r.get(p, matcher, additional)
-			if idx == -1 {
-				idx = 0
-				perfect = false
-			}
-			nodeIdxs = append(nodeIdxs, idx)
-		}
 	}
 
 	var nodes []*resolvedNode
-	for i, idx := range nodeIdxs {
-		node := &resolvedNode{
+	if len(nodeIdxs) == 0 {
+		nodes = append(nodes, &resolvedNode{
 			resolver:    r,
-			driverIndex: idx,
+			driverIndex: 0,
+		})
+	} else {
+		for i, idx := range nodeIdxs {
+			node := &resolvedNode{
+				resolver:    r,
+				driverIndex: idx,
+			}
+			if len(ps) > 0 {
+				node.platforms = []specs.Platform{ps[i]}
+			}
+			nodes = append(nodes, node)
 		}
-		if len(ps) > 0 {
-			node.platforms = []specs.Platform{ps[i]}
-		}
-		nodes = append(nodes, node)
 	}
+
 	nodes = recombineNodes(nodes)
 	if _, err := r.boot(ctx, nodeIdxs, pw); err != nil {
 		return nil, false, err
diff --git a/build/driver_test.go b/build/driver_test.go
index 63c79728..24f43411 100644
--- a/build/driver_test.go
+++ b/build/driver_test.go
@@ -217,7 +217,7 @@ func TestSelectNodePreferExact(t *testing.T) {
 	require.Equal(t, "bbb", res[0].Node().Builder)
 }
 
-func TestSelectNodeCurrentPlatform(t *testing.T) {
+func TestSelectNodeNoPlatform(t *testing.T) {
 	r := makeTestResolver(map[string][]specs.Platform{
 		"aaa": {platforms.MustParse("linux/foobar")},
 		"bbb": {platforms.DefaultSpec()},
@@ -227,7 +227,7 @@ func TestSelectNodeCurrentPlatform(t *testing.T) {
 	require.NoError(t, err)
 	require.True(t, perfect)
 	require.Len(t, res, 1)
-	require.Equal(t, "bbb", res[0].Node().Builder)
+	require.Equal(t, "aaa", res[0].Node().Builder)
 	require.Empty(t, res[0].platforms)
 }