feat(ort-utils): Support merging non-conflicting Environments

Signed-off-by: Sebastian Schuberth <[email protected]>

Author: sschuberth

model/src/main/kotlin/ScannerRun.kt

@@ -298,8 +298,8 @@ data class ScannerRun(
     /**
      * Merge this [ScannerRun] with the given [other] [ScannerRun].
      *
-     * Both [ScannerRun]s must have the same [environment] and [config], otherwise an [IllegalArgumentException] is
-     * thrown.
+     * Both [ScannerRun]s must have the same [config] and non-conflicting [environment], otherwise an
+     * [IllegalArgumentException] is thrown.
      *
      * files and scanResults are merged by their [KnownProvenance]s, while issues and scanners are merged by their
      * names.
@@ -324,11 +324,7 @@ data class ScannerRun(
         return ScannerRun(
             startTime = minOf(startTime, other.startTime),
             endTime = maxOf(endTime, other.endTime),
-            environment = environment.also {
-                require(it == other.environment) {
-                    "Cannot merge ScannerRuns with different environments: $it != ${other.environment}."
-                }
-            },
+            environment = environment + other.environment,
             config = config.also {
                 require(it == other.config) {
                     "Cannot merge ScannerRuns with different configurations: $it != ${other.config}."

model/src/test/kotlin/ScannerRunTest.kt

@@ -318,7 +318,7 @@ class ScannerRunTest : WordSpec({
             }.message shouldBe "Cannot merge ScannerRuns with different configurations: $config1 != $config2."
         }
 
-        "not merge runs with different environments" {
+        "not merge runs with conflicting environments" {
             val env1 = Environment("1.0.0", "x86_64")
             val env2 = Environment("2.0.0", "x86_64")
 
@@ -332,7 +332,8 @@ class ScannerRunTest : WordSpec({
 
             shouldThrow<IllegalArgumentException> {
                 run1 + run2
-            }.message shouldBe "Cannot merge ScannerRuns with different environments: $env1 != $env2."
+            }.message shouldBe
+                "Cannot merge Environments with different ORT versions: '${env1.ortVersion}' != '${env2.ortVersion}'."
         }
 
         "combine start and end time" {

utils/ort/src/main/kotlin/Environment.kt

@@ -112,6 +112,64 @@ data class Environment(
             "GOPATH"
         )
     }
+
+    /**
+     * Merge this [Environment] with the given [other] [Environment].
+     *
+     * Both [Environment]s must have the same properties except for [variables] and [toolVersions], otherwise an
+     * [IllegalArgumentException] is thrown.
+     */
+    operator fun plus(other: Environment) =
+        Environment(
+            ortVersion = ortVersion.also {
+                require(it == other.ortVersion) {
+                    "Cannot merge Environments with different ORT versions: '$ortVersion' != '${other.ortVersion}'."
+                }
+            },
+            buildJdk = buildJdk.also {
+                require(it == other.buildJdk) {
+                    "Cannot merge Environments with different build JDKs: '$buildJdk' != '${other.buildJdk}'."
+                }
+            },
+            javaVersion = javaVersion.also {
+                require(it == other.javaVersion) {
+                    "Cannot merge Environments with different Java versions: '$javaVersion' != '${other.javaVersion}'."
+                }
+            },
+            os = os.also {
+                require(it == other.os) {
+                    "Cannot merge Environments with different operating systems: '$os' != '${other.os}'."
+                }
+            },
+            processors = processors.also {
+                require(it == other.processors) {
+                    "Cannot merge Environments with different processor counts: '$processors' != '${other.processors}'."
+                }
+            },
+            maxMemory = maxMemory.also {
+                require(it == other.maxMemory) {
+                    "Cannot merge Environments with different memory amounts: '$maxMemory' != '${other.maxMemory}'."
+                }
+            },
+            variables = run {
+                val keyIntersection by lazy { variables.keys.intersect(other.variables.keys) }
+
+                require(variables == other.variables || keyIntersection.isEmpty()) {
+                    "Cannot merge Environments with conflicting variable keys: $keyIntersection"
+                }
+
+                variables + other.variables
+            },
+            toolVersions = run {
+                val keyIntersection by lazy { toolVersions.keys.intersect(other.toolVersions.keys) }
+
+                require(toolVersions == other.toolVersions || keyIntersection.isEmpty()) {
+                    "Cannot merge Environments with conflicting tool versions keys: $keyIntersection"
+                }
+
+                toolVersions + other.toolVersions
+            }
+        )
 }
 
 /**