Make API compatibility decisions

zipline-kotlin-plugin/src/main/kotlin/app/cash/zipline/api/compatibility/ApiCompatibilityDecision.kt

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+/*
+ * Copyright (C) 2023 Cash App
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http:https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package app.cash.zipline.api.compatibility
+
+import app.cash.zipline.api.fir.FirZiplineApi
+import app.cash.zipline.api.toml.TomlZiplineApi
+import app.cash.zipline.api.toml.TomlZiplineFunction
+import app.cash.zipline.api.toml.TomlZiplineService
+
+sealed interface ApiCompatibilityDecision
+
+class ActualApiHasProblems(
+ val messages: List<String>,
+) : ApiCompatibilityDecision
+
+class ExpectedApiRequiresUpdates(
+ val updatedApi: TomlZiplineApi,
+) : ApiCompatibilityDecision
+
+object ExpectedApiIsUpToDate : ApiCompatibilityDecision
+
+/** Compare the expected and actual API and decide what to do about it. */
+fun makeApiCompatibilityDecision(
+ expectedApi: TomlZiplineApi,
+ actualApi: FirZiplineApi,
+): ApiCompatibilityDecision {
+ val problemMessages = mutableListOf<String>()
+ var hasChanges = false
+
+ val actualServices = actualApi.services.associateBy { it.name }
+ if (actualServices.size != expectedApi.services.size) hasChanges = true
+
+ for (expectedService in expectedApi.services) {
+ val serviceName = expectedService.name
+ val actualService = actualServices[serviceName]
+
+ if (actualService == null) {
+ problemMessages +=
+ """
+ |Expected service not found:
+ | $serviceName
+ """.trimMargin()
+ continue
+ }
+
+ val actualFunctions = actualService.functions.associateBy { it.id }
+ if (actualFunctions.size != expectedService.functions.size) hasChanges = true
+
+ for (expectedFunction in expectedService.functions) {
+ val functionId = expectedFunction.id
+ val actualFunction = actualFunctions[functionId]
+ if (actualFunction == null) {
+ val comment = expectedFunction.leadingComment
+ problemMessages += buildString {
+ append("Expected function $functionId of $serviceName not found")
+ if (comment.isNotEmpty()) {
+ append(":\n ")
+ append(comment.replace("\n", "\n "))
+ }
+ }
+ }
+ }
+ }
+
+ return when {
+ problemMessages.isNotEmpty() -> ActualApiHasProblems(problemMessages)
+ hasChanges -> ExpectedApiRequiresUpdates(actualApi.toToml())
+ else -> ExpectedApiIsUpToDate
+ }
+}
+
+private fun FirZiplineApi.toToml(): TomlZiplineApi {
+ return TomlZiplineApi(
+ services.map { service ->
+ TomlZiplineService(
+ name = service.name,
+ functions = service.functions.map { function ->
+ TomlZiplineFunction(
+ leadingComment = function.signature,
+ id = function.id,
+ )
+ },
+ )
+ },
+ )
+}