Introduce "Lift return out of try" intention #KT-18830 Fixed

2017-07-08 18:24:31 +03:00
parent 8f9b680fc6
commit 8cc9330e63
38 changed files with 601 additions and 7 deletions
@@ -1,6 +1,6 @@
 <html>
 <body>
-This inspection reports if and when statements that can be converted to expressions
+This inspection reports if, when and try statements that can be converted to expressions
 by lifting return or assignment out. Typical example:
 <code><pre>
 <b>fun</b> foo(arg: Boolean): String {
@@ -30,7 +30,7 @@ class LiftReturnOrAssignmentInspection : AbstractKotlinInspection() {
    override fun buildVisitor(holder: ProblemsHolder, isOnTheFly: Boolean, session: LocalInspectionToolSession) =
            object : KtVisitorVoid() {
-                private fun visitIfOrWhen(expression: KtExpression, keyword: PsiElement) {
+                private fun visitIfOrWhenOrTry(expression: KtExpression, keyword: PsiElement) {
                    if (expression.lineCount() > LINES_LIMIT) return
                    if (expression.isElseIf()) return
@@ -60,12 +60,19 @@ class LiftReturnOrAssignmentInspection : AbstractKotlinInspection() {
                override fun visitIfExpression(expression: KtIfExpression) {
                    super.visitIfExpression(expression)
-                    visitIfOrWhen(expression, expression.ifKeyword)
+                    visitIfOrWhenOrTry(expression, expression.ifKeyword)
                }
                override fun visitWhenExpression(expression: KtWhenExpression) {
                    super.visitWhenExpression(expression)
-                    visitIfOrWhen(expression, expression.whenKeyword)
+                    visitIfOrWhenOrTry(expression, expression.whenKeyword)
                }
                override fun visitTryExpression(expression: KtTryExpression) {
                    super.visitTryExpression(expression)
                    expression.tryKeyword?.let {
                        visitIfOrWhenOrTry(expression, it)
                    }
                }
            }
@@ -21,6 +21,7 @@ import org.jetbrains.kotlin.idea.intentions.branches
 import org.jetbrains.kotlin.lexer.KtTokens
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.psi.psiUtil.anyDescendantOfType
 import org.jetbrains.kotlin.psi.psiUtil.getNonStrictParentOfType
 import org.jetbrains.kotlin.psi.psiUtil.getStrictParentOfType
 import org.jetbrains.kotlin.psi.psiUtil.lastBlockStatementOrThis
 import org.jetbrains.kotlin.types.typeUtil.isNothing
@@ -75,6 +76,12 @@ object BranchedFoldingUtils {
                    assignment != null || collectAssignmentsAndCheck(branch?.lastBlockStatementOrThis())
                }
            }
            is KtTryExpression -> {
                e.tryBlockAndCatchBodies().all {
                    val assignment = getFoldableBranchedAssignment(it)?.run { assignments.add(this) }
                    assignment != null || collectAssignmentsAndCheck(it?.lastBlockStatementOrThis())
                }
            }
            is KtCallExpression -> {
                e.analyze().getType(e)?.isNothing() ?: false
            }
@@ -83,13 +90,19 @@ object BranchedFoldingUtils {
            else -> false
        }
        if (!collectAssignmentsAndCheck(expression)) return -1
-        val firstAssignment = assignments.firstOrNull()
+        val firstAssignment = assignments.firstOrNull() ?: return 0
-        if (firstAssignment != null && assignments.any { !BranchedFoldingUtils.checkAssignmentsMatch(it, firstAssignment) }) {
+        if (assignments.any { !BranchedFoldingUtils.checkAssignmentsMatch(it, firstAssignment) }) {
            return -1
        }
        if (expression.anyDescendantOfType<KtBinaryExpression>(
                predicate = {
-                    it.operationToken in KtTokens.ALL_ASSIGNMENTS && it !in assignments
+                    if (it.operationToken in KtTokens.ALL_ASSIGNMENTS)
                        if (it.getNonStrictParentOfType<KtFinallySection>() != null)
                            BranchedFoldingUtils.checkAssignmentsMatch(it, firstAssignment)
                        else
                            it !in assignments
                    else
                        false
                }
        )) {
            return -1
@@ -128,6 +141,12 @@ object BranchedFoldingUtils {
                else -> getFoldableReturns(branches)
            }
        }
        is KtTryExpression -> {
            if (expression.finallyBlock?.finalExpression?.let { getFoldableReturns(listOf(it)) }?.isNotEmpty() == true)
                null
            else
                getFoldableReturns(expression.tryBlockAndCatchBodies())
        }
        is KtCallExpression -> {
            if (expression.analyze().getType(expression)?.isNothing() == true) emptyList() else null
        }
@@ -157,6 +176,9 @@ object BranchedFoldingUtils {
                is KtIfExpression -> e.branches.forEach { branch ->
                    getFoldableBranchedAssignment(branch)?.replaceWithRHS() ?: lift(branch?.lastBlockStatementOrThis())
                }
                is KtTryExpression -> e.tryBlockAndCatchBodies().forEach {
                    getFoldableBranchedAssignment(it)?.replaceWithRHS() ?: lift(it?.lastBlockStatementOrThis())
                }
            }
        }
        lift(expression)
@@ -177,9 +199,16 @@ object BranchedFoldingUtils {
                    getFoldableBranchedReturn(branch)?.replaceWithReturned() ?:
                    lift(branch?.lastBlockStatementOrThis())
                }
                is KtTryExpression -> e.tryBlockAndCatchBodies().forEach {
                    getFoldableBranchedReturn(it)?.replaceWithReturned() ?:
                    lift(it?.lastBlockStatementOrThis())
                }
            }
        }
        lift(expression)
        expression.replace(KtPsiFactory(expression).createExpressionByPattern("return $0", expression))
    }
    private fun KtTryExpression.tryBlockAndCatchBodies(): List<KtExpression?> = listOf(tryBlock) + catchClauses.map { it.catchBody }
 }
@@ -0,0 +1 @@
 org.jetbrains.kotlin.idea.inspections.LiftReturnOrAssignmentInspection
@@ -0,0 +1,11 @@
 // HIGHLIGHT: INFORMATION
 fun test() {
    var res: String? = null
    <caret>try {
        res = "success"
    } catch (e: Exception) {
        throw e
    }
 }
@@ -0,0 +1,11 @@
 // HIGHLIGHT: INFORMATION
 fun test() {
    var res: String? = null
    <caret>res = try {
        "success"
    } catch (e: Exception) {
        throw e
    }
 }
@@ -0,0 +1,15 @@
 // HIGHLIGHT: GENERIC_ERROR_OR_WARNING
 fun doSomething() {}
 fun test() {
    var res: String? = null
    <caret>try {
        doSomething()
        res = "success"
    } catch (e: Exception) {
        doSomething()
        res = "failure"
    }
 }
@@ -0,0 +1,15 @@
 // HIGHLIGHT: GENERIC_ERROR_OR_WARNING
 fun doSomething() {}
 fun test() {
    var res: String? = null
    <caret>res = try {
        doSomething()
        "success"
    } catch (e: Exception) {
        doSomething()
        "failure"
    }
 }
@@ -0,0 +1,18 @@
 // WITH_RUNTIME
 fun test() {
    var res: String? = null
    <caret>try {
        try {
            res = "success"
        } catch (e: Exception) {
            TODO()
        }
    } catch (e: Exception) {
        try {
            TODO()
        } catch (e: Exception) {
            res = "failure"
        }
    }
 }
@@ -0,0 +1,18 @@
 // WITH_RUNTIME
 fun test() {
    var res: String? = null
    <caret>res = try {
        try {
            "success"
        } catch (e: Exception) {
            TODO()
        }
    } catch (e: Exception) {
        try {
            TODO()
        } catch (e: Exception) {
            "failure"
        }
    }
 }
@@ -0,0 +1,13 @@
 fun doSomething() {}
 fun test() {
    var res: String? = null
    <caret>try {
        res = "success"
    } catch (e: Exception) {
        res = "failure"
    } finally {
        doSomething()
    }
 }
@@ -0,0 +1,13 @@
 fun doSomething() {}
 fun test() {
    var res: String? = null
    <caret>res = try {
        "success"
    } catch (e: Exception) {
        "failure"
    } finally {
        doSomething()
    }
 }
@@ -0,0 +1,12 @@
 // PROBLEM: none
 fun test() {
    var res: String? = null
    <caret>try {
        res = "success"
    } catch (e: Exception) {
        res = "failure"
    } finally {
        res = "finally"
    }
 }
@@ -0,0 +1,17 @@
 // PROBLEM: none
 fun doSomething() {}
 fun test(n: Int) {
    var res: String? = null
    <caret>try {
        res = "success"
    } catch (e: Exception) {
        throw e
    } finally {
        if (n == 1)
            doSomething()
        else
            res = "finally"
    }
 }
@@ -0,0 +1,17 @@
 fun doSomething() {}
 fun test(n: Int) {
    var res: String? = null
    var foo: String? = null
    <caret>try {
        res = "success"
    } catch (e: Exception) {
        throw e
    } finally {
        if (n == 1)
            doSomething()
        else
            foo = "finally"
    }
 }
@@ -0,0 +1,17 @@
 fun doSomething() {}
 fun test(n: Int) {
    var res: String? = null
    var foo: String? = null
    <caret>res = try {
        "success"
    } catch (e: Exception) {
        throw e
    } finally {
        if (n == 1)
            doSomething()
        else
            foo = "finally"
    }
 }
@@ -0,0 +1,12 @@
 fun test() {
    var res: String? = null
    var foo: String? = null
    <caret>try {
        res = "success"
    } catch (e: Exception) {
        res = "failure"
    } finally {
        foo = "finally"
    }
 }
@@ -0,0 +1,12 @@
 fun test() {
    var res: String? = null
    var foo: String? = null
    <caret>res = try {
        "success"
    } catch (e: Exception) {
        "failure"
    } finally {
        foo = "finally"
    }
 }
@@ -0,0 +1,14 @@
 fun test(n: Int) {
    var res: String? = null
    if (n == 1) {
        <caret>try {
            res = "success"
        } catch (e: Exception) {
            throw e
        }
    }
    else {
        res = "else"
    }
 }
@@ -0,0 +1,14 @@
 fun test(n: Int) {
    var res: String? = null
    if (n == 1) {
        <caret>res = try {
            "success"
        } catch (e: Exception) {
            throw e
        }
    }
    else {
        res = "else"
    }
 }
@@ -0,0 +1,11 @@
 // PROBLEM: none
 fun test() {
    var res: String? = null
    var foo: String? = null
    <caret>try {
        res = "success"
    } catch (e: Exception) {
        foo = "exception"
    }
 }
@@ -0,0 +1,13 @@
 // PROBLEM: none
 fun doSomething() {}
 fun test() {
    var res: String? = null
    <caret>try {
        res = "success"
    } catch (e: Exception) {
        res = "failure"
        doSomething()
    }
 }
@@ -0,0 +1 @@
 org.jetbrains.kotlin.idea.inspections.LiftReturnOrAssignmentInspection
@@ -0,0 +1,9 @@
 // HIGHLIGHT: INFORMATION
 fun test(): String {
    <caret>try {
        return "success"
    } catch (e: Exception) {
        throw e
    }
 }
@@ -0,0 +1,9 @@
 // HIGHLIGHT: INFORMATION
 fun test(): String {
    <caret>return try {
        "success"
    } catch (e: Exception) {
        throw e
    }
 }
@@ -0,0 +1,13 @@
 // HIGHLIGHT: GENERIC_ERROR_OR_WARNING
 fun doSomething() {}
 fun test(): String {
    <caret>try {
        doSomething()
        return "success"
    } catch (e: Exception) {
        doSomething()
        return "failure"
    }
 }
@@ -0,0 +1,13 @@
 // HIGHLIGHT: GENERIC_ERROR_OR_WARNING
 fun doSomething() {}
 fun test(): String {
    <caret>return try {
        doSomething()
        "success"
    } catch (e: Exception) {
        doSomething()
        "failure"
    }
 }
@@ -0,0 +1,16 @@
 // WITH_RUNTIME
 fun test(): String {
    <caret>try {
        try {
            return "success"
        } catch (e: Exception) {
            TODO()
        }
    } catch (e: Exception) {
        try {
            TODO()
        } catch (e: Exception) {
            return "failure"
        }
    }
 }
@@ -0,0 +1,16 @@
 // WITH_RUNTIME
 fun test(): String {
    <caret>return try {
        try {
            "success"
        } catch (e: Exception) {
            TODO()
        }
    } catch (e: Exception) {
        try {
            TODO()
        } catch (e: Exception) {
            "failure"
        }
    }
 }
@@ -0,0 +1,11 @@
 fun doSomething() {}
 fun test(): String {
    <caret>try {
        return "success"
    } catch (e: Exception) {
        return "failure"
    } finally {
        doSomething()
    }
 }
@@ -0,0 +1,11 @@
 fun doSomething() {}
 fun test(): String {
    <caret>return try {
        "success"
    } catch (e: Exception) {
        "failure"
    } finally {
        doSomething()
    }
 }
@@ -0,0 +1,14 @@
 fun doSomething() {}
 fun test(n: Int): String {
    <caret>try {
        return "success"
    } catch (e: Exception) {
        throw e
    } finally {
        if (n == 1)
            doSomething()
        else
            return "finally"
    }
 }
@@ -0,0 +1,14 @@
 fun doSomething() {}
 fun test(n: Int): String {
    return try {
        "success"
    } catch (e: Exception) {
        throw e
    } finally {
        if (n == 1)
            doSomething()
        else
            return "finally"
    }
 }
@@ -0,0 +1,10 @@
 // PROBLEM: none
 fun test(): String {
    <caret>try {
        return "success"
    } catch (e: Exception) {
        return "failure"
    } finally {
        return "finally"
    }
 }
@@ -0,0 +1,12 @@
 fun test(n: Int): String {
    if (n == 1) {
        <caret>try {
            return "success"
        } catch (e: Exception) {
            throw e
        }
    }
    else {
        return "else"
    }
 }
@@ -0,0 +1,12 @@
 fun test(n: Int): String {
    if (n == 1) {
        <caret>return try {
            "success"
        } catch (e: Exception) {
            throw e
        }
    }
    else {
        return "else"
    }
 }
@@ -0,0 +1,11 @@
 // ERROR: A 'return' expression required in a function with a block body ('{...}')
 // PROBLEM: none
 fun doSomething() {}
 fun test(): String {
    <caret>try {
        return "success"
    } catch (e: Exception) {
        doSomething()
    }
 }
@@ -629,6 +629,138 @@ public class LocalInspectionTestGenerated extends AbstractLocalInspectionTest {
            }
        }
        @TestMetadata("idea/testData/inspectionsLocal/liftOut/tryToAssignment")
        @TestDataPath("$PROJECT_ROOT")
        @RunWith(JUnit3RunnerWithInners.class)
        public static class TryToAssignment extends AbstractLocalInspectionTest {
            public void testAllFilesPresentInTryToAssignment() throws Exception {
                KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/inspectionsLocal/liftOut/tryToAssignment"), Pattern.compile("^([\\w\\-_]+)\\.kt$"), TargetBackend.ANY, true);
            }
            @TestMetadata("basic.kt")
            public void testBasic() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToAssignment/basic.kt");
                doTest(fileName);
            }
            @TestMetadata("block.kt")
            public void testBlock() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToAssignment/block.kt");
                doTest(fileName);
            }
            @TestMetadata("cascade.kt")
            public void testCascade() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToAssignment/cascade.kt");
                doTest(fileName);
            }
            @TestMetadata("finally.kt")
            public void testFinally() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToAssignment/finally.kt");
                doTest(fileName);
            }
            @TestMetadata("finallyWithAssignment.kt")
            public void testFinallyWithAssignment() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToAssignment/finallyWithAssignment.kt");
                doTest(fileName);
            }
            @TestMetadata("finallyWithCascadeAssignment.kt")
            public void testFinallyWithCascadeAssignment() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToAssignment/finallyWithCascadeAssignment.kt");
                doTest(fileName);
            }
            @TestMetadata("finallyWithCascadeUnmatchedAssignment.kt")
            public void testFinallyWithCascadeUnmatchedAssignment() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToAssignment/finallyWithCascadeUnmatchedAssignment.kt");
                doTest(fileName);
            }
            @TestMetadata("finallyWithUnmatchedAssignments.kt")
            public void testFinallyWithUnmatchedAssignments() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToAssignment/finallyWithUnmatchedAssignments.kt");
                doTest(fileName);
            }
            @TestMetadata("inner.kt")
            public void testInner() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToAssignment/inner.kt");
                doTest(fileName);
            }
            @TestMetadata("withUnmatchedAssignments.kt")
            public void testWithUnmatchedAssignments() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToAssignment/withUnmatchedAssignments.kt");
                doTest(fileName);
            }
            @TestMetadata("withoutTerminatingAssignment.kt")
            public void testWithoutTerminatingAssignment() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToAssignment/withoutTerminatingAssignment.kt");
                doTest(fileName);
            }
        }
        @TestMetadata("idea/testData/inspectionsLocal/liftOut/tryToReturn")
        @TestDataPath("$PROJECT_ROOT")
        @RunWith(JUnit3RunnerWithInners.class)
        public static class TryToReturn extends AbstractLocalInspectionTest {
            public void testAllFilesPresentInTryToReturn() throws Exception {
                KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/inspectionsLocal/liftOut/tryToReturn"), Pattern.compile("^([\\w\\-_]+)\\.kt$"), TargetBackend.ANY, true);
            }
            @TestMetadata("basic.kt")
            public void testBasic() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToReturn/basic.kt");
                doTest(fileName);
            }
            @TestMetadata("block.kt")
            public void testBlock() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToReturn/block.kt");
                doTest(fileName);
            }
            @TestMetadata("cascade.kt")
            public void testCascade() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToReturn/cascade.kt");
                doTest(fileName);
            }
            @TestMetadata("finally.kt")
            public void testFinally() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToReturn/finally.kt");
                doTest(fileName);
            }
            @TestMetadata("finallyWithCascadeReturn.kt")
            public void testFinallyWithCascadeReturn() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToReturn/finallyWithCascadeReturn.kt");
                doTest(fileName);
            }
            @TestMetadata("finallyWithReturn.kt")
            public void testFinallyWithReturn() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToReturn/finallyWithReturn.kt");
                doTest(fileName);
            }
            @TestMetadata("inner.kt")
            public void testInner() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToReturn/inner.kt");
                doTest(fileName);
            }
            @TestMetadata("withoutReturn.kt")
            public void testWithoutReturn() throws Exception {
                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/liftOut/tryToReturn/withoutReturn.kt");
                doTest(fileName);
            }
        }
        @TestMetadata("idea/testData/inspectionsLocal/liftOut/whenToAssignment")
        @TestDataPath("$PROJECT_ROOT")
        @RunWith(JUnit3RunnerWithInners.class)
		`@@ -0,0 +1 @@`
							`org.jetbrains.kotlin.idea.inspections.LiftReturnOrAssignmentInspection`