Docker: fixing a ANTLR warning (#7237)

* No A-Z a-z duplication

* Test for case insensitivity

* Comments normalization

* No need for normalization logic in subproject

* Fix normalization logic for Windows backward slashes

Author: greg-at-moderne

build.gradle.kts

@@ -31,7 +31,7 @@ subprojects {
             doLast {
                 val idx = args?.indexOf("-o") ?: return@doLast
                 if (idx < 0 || idx + 1 >= args!!.size) return@doLast
-                val rootPrefix = rootProject.projectDir.absolutePath + "/"
+                val rootPrefix = rootProject.projectDir.absolutePath.replace("\\", "/") + "/"
                 val year = Calendar.getInstance().get(Calendar.YEAR)
                 val licenseHeader = "/*\n" + rootProject.file("gradle/licenseHeader.txt")
                     .readText().trim()

rewrite-docker/src/main/antlr/DockerLexer.g4

@@ -89,7 +89,7 @@ EQUALS     : '=' { if (!afterHealthcheck) atLineStart = false; };
 // Captures the entire flag as a single token, stopping at whitespace
 // This avoids the greedy flagValue+ parsing issue while keeping shell commands working
 // Flag values can contain quoted strings (which may include spaces)
-FLAG : '--' [a-zA-Z] [a-zA-Z0-9_-]* ('=' FLAG_VALUE_PART+)? { if (!afterHealthcheck) atLineStart = false; };
+FLAG : '--' [a-z] [a-z0-9_-]* ('=' FLAG_VALUE_PART+)? { if (!afterHealthcheck) atLineStart = false; };
 fragment FLAG_VALUE_PART
     : '"' ( '\\' ~[\r\n] | ~["\\\r\n] )* '"'   // Double-quoted string (with escapes)
     | '\'' ~['\r\n]* '\''                        // Single-quoted string (literal)

rewrite-docker/src/main/java/org/openrewrite/docker/internal/grammar/DockerLexer.java

@@ -13,7 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-// Generated from C:/Users/sambs/projects/openrewrite/rewrite/rewrite-docker/src/main/antlr/DockerLexer.g4 by ANTLR 4.13.2
+// Generated from rewrite-docker/src/main/antlr/DockerLexer.g4 by ANTLR 4.13.2
 package org.openrewrite.docker.internal.grammar;
 import java.util.LinkedList;
 import java.util.Queue;

rewrite-docker/src/main/java/org/openrewrite/docker/internal/grammar/DockerParser.java

@@ -13,7 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-// Generated from C:/Users/sambs/projects/openrewrite/rewrite/rewrite-docker/src/main/antlr/DockerParser.g4 by ANTLR 4.13.2
+// Generated from rewrite-docker/src/main/antlr/DockerParser.g4 by ANTLR 4.13.2
 package org.openrewrite.docker.internal.grammar;
 import org.antlr.v4.runtime.atn.*;
 import org.antlr.v4.runtime.dfa.DFA;

rewrite-docker/src/main/java/org/openrewrite/docker/internal/grammar/DockerParserBaseListener.java

@@ -13,7 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-// Generated from C:/Users/sambs/projects/openrewrite/rewrite/rewrite-docker/src/main/antlr/DockerParser.g4 by ANTLR 4.13.2
+// Generated from rewrite-docker/src/main/antlr/DockerParser.g4 by ANTLR 4.13.2
 package org.openrewrite.docker.internal.grammar;
 
 import org.antlr.v4.runtime.ParserRuleContext;

rewrite-docker/src/main/java/org/openrewrite/docker/internal/grammar/DockerParserBaseVisitor.java

@@ -13,7 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-// Generated from C:/Users/sambs/projects/openrewrite/rewrite/rewrite-docker/src/main/antlr/DockerParser.g4 by ANTLR 4.13.2
+// Generated from rewrite-docker/src/main/antlr/DockerParser.g4 by ANTLR 4.13.2
 package org.openrewrite.docker.internal.grammar;
 import org.antlr.v4.runtime.tree.AbstractParseTreeVisitor;
 

rewrite-docker/src/main/java/org/openrewrite/docker/internal/grammar/DockerParserListener.java

@@ -13,7 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-// Generated from C:/Users/sambs/projects/openrewrite/rewrite/rewrite-docker/src/main/antlr/DockerParser.g4 by ANTLR 4.13.2
+// Generated from rewrite-docker/src/main/antlr/DockerParser.g4 by ANTLR 4.13.2
 package org.openrewrite.docker.internal.grammar;
 import org.antlr.v4.runtime.tree.ParseTreeListener;
 

rewrite-docker/src/main/java/org/openrewrite/docker/internal/grammar/DockerParserVisitor.java

@@ -13,7 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-// Generated from C:/Users/sambs/projects/openrewrite/rewrite/rewrite-docker/src/main/antlr/DockerParser.g4 by ANTLR 4.13.2
+// Generated from rewrite-docker/src/main/antlr/DockerParser.g4 by ANTLR 4.13.2
 package org.openrewrite.docker.internal.grammar;
 import org.antlr.v4.runtime.tree.ParseTreeVisitor;
 

rewrite-docker/src/test/java/org/openrewrite/docker/DockerParserTest.java

@@ -86,6 +86,22 @@ void comprehensiveDockerfile() {
         );
     }
 
+    @Test
+    void caseInsensitiveInstructions() {
+        rewriteRun(
+          docker(
+            """
+              from ubuntu:20.04
+              run apt-get update
+              copy app.jar /app/
+              Env MY_VAR=value
+              expose 8080
+              Cmd ["./app"]
+              """
+          )
+        );
+    }
+
     @Test
     void multipleJsonArrayWhitespaceStyles() {
         // Test different whitespace styles in JSON arrays are preserved