terraform apply crashes if a variable's default is set to a list

[spenczar]

If you set a variable’s default to a list, then terraform apply exits with an ugly crash.

Here’s my test case:

1. Make a new directory and cd into it:

   $ cd $(mktemp -d -t terraformtest)

2. Make a testcase terraform config:

   $ cat > test.tf  << EOF
   variable "testcase" {
   default {
     l = [1, 2, 3]
   }
   }
   EOF

3. Try running terraform apply:

   $ terraform apply
   panic: Unknown variable type: 0x0
   
   goroutine 1 [running]:
   github.com/hashicorp/terraform/terraform.(*Context).Input(0xc208094b00, 0xc208094b07, 0x0, 0x0)
   /Users/spencer/go/src/github.com/hashicorp/terraform/terraform/context.go:175 +0xc61
   github.com/hashicorp/terraform/command.(*ApplyCommand).Run(0xc2080641c0, 0xc20800a010, 0x0, 0x0, 0xc2080368a8)
   /Users/spencer/go/src/github.com/hashicorp/terraform/command/apply.go:125 +0x11a6
   github.com/mitchellh/cli.(*CLI).Run(0xc20806a500, 0xc2080d8ae0, 0x0, 0x0)
   /Users/spencer/go/src/github.com/mitchellh/cli/cli.go:100 +0x3ce
   main.wrappedMain(0x0)
   /Users/spencer/go/src/github.com/hashicorp/terraform/main.go:150 +0xb76
   main.realMain(0x0)
   /Users/spencer/go/src/github.com/hashicorp/terraform/main.go:82 +0x923
   main.main()
   /Users/spencer/go/src/github.com/hashicorp/terraform/main.go:18 +0x1f
   
   goroutine 5 [syscall]:
   os/signal.loop()
   /usr/local/Cellar/go/1.4.2/libexec/src/os/signal/signal_unix.go:21 +0x1f
   created by os/signal.init·1
   /usr/local/Cellar/go/1.4.2/libexec/src/os/signal/signal_unix.go:27 +0x35
   
   goroutine 8 [chan receive]:
   main.func·014()
   /Users/spencer/go/src/github.com/hashicorp/terraform/commands.go:134 +0x52
   created by main.makeShutdownCh
   /Users/spencer/go/src/github.com/hashicorp/terraform/commands.go:137 +0x1b4
   
   goroutine 9 [semacquire]:
   sync.(*Cond).Wait(0xc2080d4330)
   /usr/local/Cellar/go/1.4.2/libexec/src/sync/cond.go:62 +0x9e
   io.(*pipe).read(0xc2080d4300, 0xc20809f000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
   /usr/local/Cellar/go/1.4.2/libexec/src/io/pipe.go:52 +0x303
   io.(*PipeReader).Read(0xc2080441b0, 0xc20809f000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
   /usr/local/Cellar/go/1.4.2/libexec/src/io/pipe.go:134 +0x5b
   bufio.(*Scanner).Scan(0xc208066300, 0x0)
   /usr/local/Cellar/go/1.4.2/libexec/src/bufio/scan.go:180 +0x688
   github.com/hashicorp/terraform/command.func·006()
   /Users/spencer/go/src/github.com/hashicorp/terraform/command/meta.go:293 +0x3d
   created by github.com/hashicorp/terraform/command.(*Meta).flagSet
   /Users/spencer/go/src/github.com/hashicorp/terraform/command/meta.go:296 +0x51f
   
   
   
   !!!!!!!!!!!!!!!!!!!!!!!!!!! TERRAFORM CRASH !!!!!!!!!!!!!!!!!!!!!!!!!!!!
   
   Terraform crashed! This is always indicative of a bug within Terraform.
   A crash log has been placed at “crash.log” relative to your current
   working directory. It would be immensely helpful if you could please
   report the crash with Terraform[1] so that we can fix this.
   
   
   
   !!!!!!!!!!!!!!!!!!!!!!!!!!! TERRAFORM CRASH !!!!!!!!!!!!!!!!!!!!!!!!!!!!

I stumbled on this while crossing my fingers that I could set a default to a list of CIDR blocks to whitelist in an AWS security group. I’m fine with lists being verboten, but the error should be clearer.

[mitchellh]

Is this with master?

[spenczar]

It's on 19d6fdf, which is from Mon Mar 30 15:01:04.

I just noticed something got frazzled in writing this issue though - those are unicode quotation marks in my step 2. I had “testcase”, but it should be "testcase" of course. Try again now.

[mitchellh]

Fixed in PR #1590. Thanks.

[ghost]

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