Simple:
  - name: 'Define only'
    input:
      type: raw
      value: 'proc test {} {}'
  - name: 'Define with content'
    input:
      type: raw
      value: 'proc test {} {puts hi}'
  - name: 'Define with content and argument'
    input:
      type: raw
      value: 'proc test {sup} {puts $sup}'
  - name: 'Define with content and arguments'
    input:
      type: raw
      value: 'proc test {a b} {puts "$a$b"}'

Running:
  - name: 'Execute'
    input:
      type: raw
      value: 'proc run {} {puts "Hello World!"}; run'
    stdout:
      type: raw
      value: "Hello World!\n"
  - name: 'Execute with argument'
    input:
      type: raw
      value: 'proc run {thing} {puts "Hello $thing!"}; run World'
    stdout:
      type: raw
      value: "Hello World!\n"
  - name: 'Execute with arguments'
    input:
      type: raw
      value: 'proc run {a b} {puts "$a $b!"}; run Hello World'
    stdout:
      type: raw
      value: "Hello World!\n"
  - name: 'Error on invalid amount'
    input:
      type: raw
      value: 'proc run {a b} {puts "$a $b!"}; run Hello'
    output:
      type: error
      value: 'wrong # args on procedure "run"'