Verifying and Compiling Examples

Verifying Examples

Stainless is currently available as either:

  • a command line tool, which exposes most of the functionality, available as a ZIP file (recommended) or via Docker.

  • via an SBT plugin.

See the installation documentation for more information.

It is henceforth assumed that there exists a stainless script in in your PATH.

To see the main options, use

$ stainless --help

in your command line shell. You may also wish to consult the available command-line options.

You can try some of the examples from frontends/benchmarks distributed with Stainless:

$ stainless --solvers=smt-cvc4 frontends/benchmarks/verification/invalid/InsertionSort.scala

and get something like this (some output cropped)

[  Info  ] Starting verification...
[  Info  ] Verified: 3 / 19
[Warning ]  - Result for 'postcondition' VC for buggySortedIns @37:38:
[Warning ] l.isInstanceOf[Nil] || !(l.head <= e) || {
[Warning ]   val res: List = Cons(l.head, buggySortedIns(e, l.tail))
[Warning ]   assume({
[Warning ]     val e: List = Cons(l.head, buggySortedIns(e, l.tail))
[Warning ]     true
[Warning ]   })
[Warning ]   contents(res) == contents(l) ++ Set(e) && isSorted(res) && size(res) == size(l) + BigInt("1")
[Warning ] }
[Warning ] frontends/benchmarks/verification/invalid/InsertionSort.scala:37:38:  => INVALID
                 case Cons(x,xs) => if (x <= e) Cons(x,buggySortedIns(e, xs)) else Cons(e, l)
                                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[Warning ] Found counter-example:
[Warning ]   l: List -> Cons(-770374653, Cons(-771685886, Nil()))
[Warning ]   e: Int  -> 1376322050
[  Info  ] Verified: 3 / 19
[Warning ]  - Result for 'postcondition' VC for buggySortedIns @37:73:
[Warning ] l.isInstanceOf[Nil] || l.head <= e || {
[Warning ]   val res: List = Cons(e, l)
[Warning ]   contents(res) == contents(l) ++ Set(e) && isSorted(res) && size(res) == size(l) + BigInt("1")
[Warning ] }
[Warning ] frontends/benchmarks/verification/invalid/InsertionSort.scala:37:73:  => INVALID
                 case Cons(x,xs) => if (x <= e) Cons(x,buggySortedIns(e, xs)) else Cons(e, l)
                                                                                   ^^^^^^^^^^
[Warning ] Found counter-example:
[Warning ]   l: List -> Cons(691483681, Cons(512, Nil()))
[Warning ]   e: Int  -> -1263292350
[  Info  ] Verified: 17 / 19
[  Info  ]   ┌───────────────────┐
[  Info  ] ╔═╡ stainless summary ╞══════════════════════════════════════════════════════════════════════════════════════════════╗
[  Info  ] ║ └───────────────────┘                                                                                              ║
[  Info  ] ║ InsertionSort.scala:33:7:    buggySortedIns  non-negative measure                  valid             U:smt-z3  0,1 ║
[  Info  ] ║ InsertionSort.scala:35:5:    buggySortedIns  body assertion: match exhaustiveness  trivial                     0,0 ║
[  Info  ] ║ InsertionSort.scala:35:5:    buggySortedIns  postcondition                         trivial                     0,0 ║
[  Info  ] ║ InsertionSort.scala:36:21:   buggySortedIns  postcondition                         valid             U:smt-z3  0,1 ║
[  Info  ] ║ InsertionSort.scala:37:38:   buggySortedIns  postcondition                         invalid           U:smt-z3  0,3 ║
[  Info  ] ║ InsertionSort.scala:37:45:   buggySortedIns  measure decreases                     valid             U:smt-z3  0,1 ║
[  Info  ] ║ InsertionSort.scala:37:73:   buggySortedIns  postcondition                         invalid           U:smt-z3  0,1 ║
[  Info  ] ║ InsertionSort.scala:20:7:    contents        non-negative measure                  valid from cache            0,0 ║
[  Info  ] ║ InsertionSort.scala:20:37:   contents        body assertion: match exhaustiveness  trivial                     0,0 ║
[  Info  ] ║ InsertionSort.scala:22:24:   contents        measure decreases                     valid             U:smt-z3  0,0 ║
[  Info  ] ║ InsertionSort.scala:25:7:    isSorted        non-negative measure                  valid             U:smt-z3  0,0 ║
[  Info  ] ║ InsertionSort.scala:25:36:   isSorted        body assertion: match exhaustiveness  trivial                     0,0 ║
[  Info  ] ║ InsertionSort.scala:28:44:   isSorted        measure decreases                     valid             U:smt-z3  0,1 ║
[  Info  ] ║ InsertionSort.scala:15:7:    size            non-negative measure                  valid from cache            0,0 ║
[  Info  ] ║ InsertionSort.scala:15:34:   size            body assertion: match exhaustiveness  trivial                     0,0 ║
[  Info  ] ║ InsertionSort.scala:15:34:   size            postcondition                         trivial                     0,0 ║
[  Info  ] ║ InsertionSort.scala:16:19:   size            postcondition                         valid             U:smt-z3  0,0 ║
[  Info  ] ║ InsertionSort.scala:17:25:   size            postcondition                         valid             U:smt-z3  0,0 ║
[  Info  ] ║ InsertionSort.scala:17:29:   size            measure decreases                     valid from cache            0,0 ║
[  Info  ] ╟┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄╢
[  Info  ] ║ total: 19   valid: 17   (3 from cache, 6 trivial) invalid: 2    unknown: 0    time:    0,81                        ║
[  Info  ] ╚════════════════════════════════════════════════════════════════════════════════════════════════════════════════════╝
[  Info  ] Verification pipeline summary:
[  Info  ]   cache, anti-aliasing, smt-z3
[  Info  ] Shutting down executor service.

Compiling and Executing Examples

Scala code written with Stainless library dependencies can be compiled and run using the library sources available on the Stainless github repository, along with the scala compiler and runner script.

scalac -d /some_folder_for_compiled_classes/ $(find /path/to/stainless/frontends/library/stainless/ -name "*.scala") File1.scala File2.scala ...
scala -cp /some_folder_for_compiled_classes/ $(find /path/to/stainless/frontends/library/stainless/ -name "*.scala") MainClassName