Ensure that ParsedDockerfile supports platform args (#2780)

Author: rnorth

core/src/main/java/org/testcontainers/images/ParsedDockerfile.java

@@ -21,7 +21,7 @@
 @Slf4j
 public class ParsedDockerfile {
 
-    private static final Pattern FROM_LINE_PATTERN = Pattern.compile("FROM ([^\\s]+).*");
+    private static final Pattern FROM_LINE_PATTERN = Pattern.compile("FROM (?<arg>--[^\\s]+\\s)*(?<image>[^\\s]+).*", Pattern.CASE_INSENSITIVE);
 
     private final Path dockerFilePath;
 
@@ -57,7 +57,7 @@ private void parse(List<String> lines) {
         dependencyImageNames = lines.stream()
             .map(FROM_LINE_PATTERN::matcher)
             .filter(Matcher::matches)
-            .map(matcher -> matcher.group(1))
+            .map(matcher -> matcher.group("image"))
             .collect(Collectors.toSet());
 
         if (!dependencyImageNames.isEmpty()) {

core/src/test/java/org/testcontainers/images/ParsedDockerfileTest.java

@@ -16,6 +16,12 @@ public void doesSimpleParsing() {
         assertEquals("extracts a single image name", Sets.newHashSet("someimage"), parsedDockerfile.getDependencyImageNames());
     }
 
+    @Test
+    public void isCaseInsensitive() {
+        final ParsedDockerfile parsedDockerfile = new ParsedDockerfile(asList("from someimage", "RUN something"));
+        assertEquals("extracts a single image name", Sets.newHashSet("someimage"), parsedDockerfile.getDependencyImageNames());
+    }
+
     @Test
     public void handlesTags() {
         final ParsedDockerfile parsedDockerfile = new ParsedDockerfile(asList("FROM someimage:tag", "RUN something"));
@@ -40,6 +46,18 @@ public void ignoringBuildStageNames() {
         assertEquals("ignores build stage names and allows multiple images to be extracted", Sets.newHashSet("someimage", "nextimage"), parsedDockerfile.getDependencyImageNames());
     }
 
+    @Test
+    public void ignoringPlatformArgs() {
+        final ParsedDockerfile parsedDockerfile = new ParsedDockerfile(asList("FROM --platform=linux/amd64 someimage", "RUN something"));
+               assertEquals("ignores platform args", Sets.newHashSet("someimage"), parsedDockerfile.getDependencyImageNames());
+    }
+
+    @Test
+    public void ignoringExtraPlatformArgs() {
+        final ParsedDockerfile parsedDockerfile = new ParsedDockerfile(asList("FROM --platform=linux/amd64 --somethingelse=value someimage", "RUN something"));
+               assertEquals("ignores platform args", Sets.newHashSet("someimage"), parsedDockerfile.getDependencyImageNames());
+    }
+
     @Test
     public void handlesGracefullyIfNoFromLine() {
         final ParsedDockerfile parsedDockerfile = new ParsedDockerfile(asList("RUN something", "# is this even a valid Dockerfile?"));