1 commit

Author	SHA1	Message	Date
Anna Shaleva	07ee7f7e12	compiler: allow multi-return variables declaration ... Problem: an attempt to compile the following code leads to a runtime panic: ``` package foo var a, b = f() func Main() int { return a + b } func f() (int, int) { return 1, 2 } ``` ``` panic: runtime error: index out of range [1] with length 1 [recovered] panic: runtime error: index out of range [1] with length 1 goroutine 22 [running]: testing.tRunner.func1.2({0xa341c0, 0xc0001647f8}) /usr/local/go/src/testing/testing.go:1209 +0x24e testing.tRunner.func1() /usr/local/go/src/testing/testing.go:1212 +0x218 panic({0xa341c0, 0xc0001647f8}) /usr/local/go/src/runtime/panic.go:1038 +0x215 github.com/nspcc-dev/neo-go/pkg/compiler.(*codegen).Visit(0xc0001623c0, {0xc75520, 0xc000155d80}) /home/anna/Documents/GitProjects/nspcc-dev/neo-go/pkg/compiler/codegen.go:591 +0x6559 go/ast.Walk({0xc6c4e0, 0xc0001623c0}, {0xc75520, 0xc000155d80}) /usr/local/go/src/go/ast/walk.go:50 +0x5f github.com/nspcc-dev/neo-go/pkg/compiler.(*codegen).convertGlobals.func1({0xc75520, 0xc000155d80}) /home/anna/Documents/GitProjects/nspcc-dev/neo-go/pkg/compiler/codegen.go:359 +0x70 go/ast.inspector.Visit(0xc000229740, {0xc75520, 0xc000155d80}) /usr/local/go/src/go/ast/walk.go:375 +0x31 go/ast.Walk({0xc6d920, 0xc000229740}, {0xc75520, 0xc000155d80}) /usr/local/go/src/go/ast/walk.go:50 +0x5f go/ast.walkDeclList({0xc6d920, 0xc000229740}, {0xc000155e80, 0x3, 0x120}) /usr/local/go/src/go/ast/walk.go:36 +0x87 go/ast.Walk({0xc6d920, 0xc000229740}, {0xc75458, 0xc000156c80}) /usr/local/go/src/go/ast/walk.go:355 +0x15c5 go/ast.Inspect(...) /usr/local/go/src/go/ast/walk.go:387 github.com/nspcc-dev/neo-go/pkg/compiler.(*codegen).convertGlobals(0xc0001623c0, 0xc000156c80, 0xc000254280) /home/anna/Documents/GitProjects/nspcc-dev/neo-go/pkg/compiler/codegen.go:354 +0x71 github.com/nspcc-dev/neo-go/pkg/compiler.(*codegen).traverseGlobals.func2(0xc000254280) /home/anna/Documents/GitProjects/nspcc-dev/neo-go/pkg/compiler/analysis.go:86 +0x16e github.com/nspcc-dev/neo-go/pkg/compiler.(*codegen).ForEachPackage(0xc0001623c0, 0xc000191b98) /home/anna/Documents/GitProjects/nspcc-dev/neo-go/pkg/compiler/compiler.go:93 +0xc6 github.com/nspcc-dev/neo-go/pkg/compiler.(*codegen).traverseGlobals(0xc0001623c0) /home/anna/Documents/GitProjects/nspcc-dev/neo-go/pkg/compiler/analysis.go:82 +0x22c github.com/nspcc-dev/neo-go/pkg/compiler.(*codegen).compile(0xc0001623c0, 0xc000274d20, 0x1) /home/anna/Documents/GitProjects/nspcc-dev/neo-go/pkg/compiler/codegen.go:2118 +0x17c github.com/nspcc-dev/neo-go/pkg/compiler.codeGen(0xc000274d20) /home/anna/Documents/GitProjects/nspcc-dev/neo-go/pkg/compiler/codegen.go:2191 +0x353 github.com/nspcc-dev/neo-go/pkg/compiler.CompileWithOptions({0xa6f39a, 0xc00023cee0}, {0xc6d240, 0xc00024a460}, 0x0) /home/anna/Documents/GitProjects/nspcc-dev/neo-go/pkg/compiler/compiler.go:218 +0x65 github.com/nspcc-dev/neo-go/pkg/compiler_test.vmAndCompileInterop(0x5648df, {0xa9989f, 0x7d}) /home/anna/Documents/GitProjects/nspcc-dev/neo-go/pkg/compiler/vm_test.go:75 +0x113 github.com/nspcc-dev/neo-go/pkg/compiler_test.eval(0xc00024a440, {0xa9989f, 0x129f366e}, {0xa68880, 0xc00024a440}) /home/anna/Documents/GitProjects/nspcc-dev/neo-go/pkg/compiler/vm_test.go:36 +0x2d github.com/nspcc-dev/neo-go/pkg/compiler_test.TestGenDeclWithMultiRet.func2(0x4079f9) /home/anna/Documents/GitProjects/nspcc-dev/neo-go/pkg/compiler/global_test.go:36 +0x4f testing.tRunner(0xc00022e9c0, 0xbce760) /usr/local/go/src/testing/testing.go:1259 +0x102 created by testing.(*T).Run /usr/local/go/src/testing/testing.go:1306 +0x35a ``` Solution: Allow using multi-return function calls as general variable declaration value. It was supported for assignment statements, so do the same for *ast.GenDecl if it's a variable under the hood.	2022-08-16 15:33:44 +03:00