From 579b61c06ff6fd0a5cbce8a86a50ad700a5314fa Mon Sep 17 00:00:00 2001
From: Simon Brown <simon@structurizr.com>
Date: Sun, 2 Apr 2023 09:35:52 +0100
Subject: [PATCH] Fixes https://github.com/structurizr/dsl/issues/241 (Allow
 styles defined in an extending workspace to override those in the base
 workspace).

---
 docs/changelog.md                                          | 4 ++++
 src/main/java/com/structurizr/dsl/ElementStyleParser.java  | 7 ++++++-
 .../java/com/structurizr/dsl/RelationshipStyleParser.java  | 7 ++++++-
 .../java/com/structurizr/dsl/ElementStyleParserTests.java  | 6 ++++++
 .../com/structurizr/dsl/RelationshipStyleParserTests.java  | 6 ++++++
 5 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/docs/changelog.md b/docs/changelog.md
index 9feaef4..587ae01 100644
--- a/docs/changelog.md
+++ b/docs/changelog.md
@@ -1,5 +1,9 @@
 # Changelog
 
+## (unreleased)
+
+- Fixes https://github.com/structurizr/dsl/issues/241 (Allow styles defined in an extending workspace to override those in the base workspace).
+
 ## 1.30.0 (31st March 2023)
 
 - Allows `deploymentEnvironment` to be used without starting a new context (i.e. without `{` and `}`) (see https://github.com/structurizr/cli/discussions/112).
diff --git a/src/main/java/com/structurizr/dsl/ElementStyleParser.java b/src/main/java/com/structurizr/dsl/ElementStyleParser.java
index cdea135..1769ec5 100644
--- a/src/main/java/com/structurizr/dsl/ElementStyleParser.java
+++ b/src/main/java/com/structurizr/dsl/ElementStyleParser.java
@@ -27,7 +27,12 @@ ElementStyle parseElementStyle(DslContext context, Tokens tokens) {
             }
 
             Workspace workspace = context.getWorkspace();
-            return workspace.getViews().getConfiguration().getStyles().addElementStyle(tag);
+            ElementStyle elementStyle = workspace.getViews().getConfiguration().getStyles().getElementStyle(tag);
+            if (elementStyle == null) {
+                elementStyle = workspace.getViews().getConfiguration().getStyles().addElementStyle(tag);
+            }
+
+            return elementStyle;
         } else {
             throw new RuntimeException("Expected: element <tag> {");
         }
diff --git a/src/main/java/com/structurizr/dsl/RelationshipStyleParser.java b/src/main/java/com/structurizr/dsl/RelationshipStyleParser.java
index bfb295f..6c260c3 100644
--- a/src/main/java/com/structurizr/dsl/RelationshipStyleParser.java
+++ b/src/main/java/com/structurizr/dsl/RelationshipStyleParser.java
@@ -26,7 +26,12 @@ RelationshipStyle parseRelationshipStyle(DslContext context, Tokens tokens) {
             }
 
             Workspace workspace = context.getWorkspace();
-            return workspace.getViews().getConfiguration().getStyles().addRelationshipStyle(tag);
+            RelationshipStyle relationshipStyle = workspace.getViews().getConfiguration().getStyles().getRelationshipStyle(tag);
+            if (relationshipStyle == null) {
+                relationshipStyle = workspace.getViews().getConfiguration().getStyles().addRelationshipStyle(tag);
+            }
+
+            return relationshipStyle;
         } else {
             throw new RuntimeException("Expected: relationship <tag> {");
         }
diff --git a/src/test/java/com/structurizr/dsl/ElementStyleParserTests.java b/src/test/java/com/structurizr/dsl/ElementStyleParserTests.java
index d5cf245..5216eb3 100644
--- a/src/test/java/com/structurizr/dsl/ElementStyleParserTests.java
+++ b/src/test/java/com/structurizr/dsl/ElementStyleParserTests.java
@@ -60,6 +60,12 @@ void test_parseElementStyle_CreatesAnElementStyle() {
         assertNotNull(style);
     }
 
+    @Test
+    void test_parseElementStyle_FindsAnExistingElementStyle() {
+        ElementStyle style = workspace.getViews().getConfiguration().getStyles().addElementStyle("Tag");
+        assertSame(style, parser.parseElementStyle(context(), tokens("element", "Tag")));
+    }
+
     @Test
     void test_parseShape_ThrowsAnException_WhenThereAreTooManyTokens() {
         try {
diff --git a/src/test/java/com/structurizr/dsl/RelationshipStyleParserTests.java b/src/test/java/com/structurizr/dsl/RelationshipStyleParserTests.java
index 14ce429..8736c5a 100644
--- a/src/test/java/com/structurizr/dsl/RelationshipStyleParserTests.java
+++ b/src/test/java/com/structurizr/dsl/RelationshipStyleParserTests.java
@@ -59,6 +59,12 @@ void test_parseRelationshipStyle_CreatesAnRelationshipStyle() {
         assertNotNull(style);
     }
 
+    @Test
+    void test_parseRelationshipStyle_FindsAnExistingRelationshipStyle() {
+        RelationshipStyle style = workspace.getViews().getConfiguration().getStyles().addRelationshipStyle("Tag");
+        assertSame(style, parser.parseRelationshipStyle(context(), tokens("relationship", "Tag")));
+    }
+
     @Test
     void test_parseThickness_ThrowsAnException_WhenThereAreTooManyTokens() {
         try {