Added initial specification of addition and subtraction of integers

.gitignore

@@ -1,2 +1,8 @@
 Smalltalk/SOMCore.csp
-
+specification/*.class
+specification/*.java
+specification/*.tokens
+specification/*.interp
+specification/are-we-fast-yet
+specification/*.jar
+/SOM

.travis.yml

@@ -54,7 +54,7 @@ jobs:
       name: ykSOM
       dist: bionic
       rust: [nightly]
-      env: REPO=yksom.git  BUILD="cargo build"  SOM="cargo run -- " SOM_TESTS="--cp ../Smalltalk ../TestSuite/TestHarness.som"
+      env: REPO=yksom.git  BUILD="cargo build"  SOM="cargo run -- " SOM_TESTS="--cp ../Smalltalk ../TestSuite/TestHarness.som" SOM_SPECS="--cp ../Smalltalk:../TestSuite:../specification/executable_specs ../specification/executable_specs/AllSpecs.som"
 
 
   # allow_failures:
@@ -105,4 +105,13 @@ script:
 
       echo "$SOM $SOM_TESTS"
       eval "$SOM $SOM_TESTS"
+
+      echo Run Specs
+      if [ "$SOM_SPECS" == "" ]
+      then
+        export SOM_SPECS="-cp ../Smalltalk:../TestSuite:../specification/executable_specs AllSpecs"
+      fi
+
+      echo "$SOM $SOM_SPECS"
+      eval "$SOM $SOM_SPECS"
     fi

Smalltalk/Object.som

@@ -103,4 +103,14 @@ Object = nil (
     instVarAt: idx put: obj = primitive
     instVarNamed: sym       = primitive
 
+    isKindOf: class = (
+      | superclass |
+      self class == class ifTrue: [ ^ true ].
+
+
+      [(superclass := self class superclass) == nil] whileFalse: [
+        superclass == class ifTrue: [ ^ true ] ].
+
+      ^ false
+    )
 )

TestSuite/TestHarness.som

@@ -95,15 +95,29 @@ TestHarness = (
     )
 
     runOneSuite: name = (
-      | testName runner |
+      | testName runner totalTestNum successfulTestNum unsupportedTestNum totalAssertionNum |
       testName := name.
-      (testName endsWith: 'Test') ifFalse: [
+      ((testName endsWith: 'Test') or: [testName endsWith: 'Spec']) ifFalse: [
         testName := testName + 'Test'].
 
       runner := TestRunner new.
       runner initializeOn: (system resolve: testName asSymbol).
       runner run.
-      runner hasFailures ifTrue: [system exit: 1]
+
+      totalTestNum       := runner expectedPasses.
+      unsupportedTestNum := runner actualUnsupported.
+      successfulTestNum  := runner actualPasses.
+      totalAssertionNum  := runner numAsserts.
+
+      'Number of unsupported optionals: ' print.
+      unsupportedTestNum println.
+      'Number of assertions tested:     ' print.
+      totalAssertionNum println.
+
+      (failOnUnsupportedOptionals and: [unsupportedTestNum > 0])
+        ifTrue: [system exit: 1].
+      totalTestNum = successfulTestNum
+        ifFalse: [system exit: 1].
     )
 
     run: args = (

specification/executable_specs/AllSpecs.som

@@ -0,0 +1,9 @@
+AllSpecs = TestHarness (
+  tests = (
+    | l1 |
+    l1 := Vector new.
+    l1 append: IntSpec.
+    ^ l1
+  )
+
+)

specification/executable_specs/Specification.som

@@ -0,0 +1,27 @@
+Specification = TestCase (
+
+  expect: actual toEqual: expected = (
+    self assert: expected = actual
+         description: [self comparingStringBetween: expected and: actual]
+  )
+
+  expect: actual toBe: expected = (
+    self assert: actual == expected
+         description: [self comparingStringBetween: expected and: actual]
+  )
+
+  expect: actual toEqual: double within: epsilon = (
+    self assert: double - actual < epsilon
+         description: ['Expected ' + actual asString + ' to equal ' + double asString + ' within: ' + epsilon asString]
+  )
+
+  expect: actual toBeGreaterThan: expected = (
+    self assert: actual > expected
+         description: ['Expected ' + actual asString + ' to be greater than ' + expected]
+  )
+
+  expect: actual toBeKindOf: class = (
+    self assert: (actual isKindOf: class)
+         description: ['Expected ' +  actual asString + ' to be of class ' + class asString]
+  )
+)

specification/index.md

@@ -0,0 +1,96 @@
+# Simple Object Machine
+
+## Language Specification
+
+### Introduction
+
+[SOM][SOM-st] is a minimal Smalltalk dialect which was used to teach VM
+construction at the [Hasso Plattner Institute][SOM]. It was originally built at
+the University of Århus (Denmark) for teaching.
+
+Currently, SOM is maintained as a research and teaching tool and has its home
+at: [https://som-st.github.io][SOM-st]
+
+
+### Core Library
+
+#### Integer Class
+
+Integers in SOM have arbitrary precision, which means they are not strictly
+word-sized or indeed have any other upper limited than the available memory.
+
+All integers are an instance of class `Integer`.
+
+In the following, we define all operations on `Integer`.
+
+##### Addition
+
+The addition of arbitrary-precision integers returns an arbitrary-precision
+integer.
+
+For example:
+
+```{spec IntSpec.intAddition}
+ 3 + 4 = 7.
+-4 + 3 = -1.
+```
+
+The addition of a `Double` value to an integer results in a `Double` value.
+
+For example:
+
+```{spec IntSpec.doubleAddition}
+self expect:  3 + 4.4 toEqual:  7.4 within: 0.00000001.
+self expect: -4 + 3.3 toEqual: -0.7 within: 0.00000001.
+```
+
+Furthermore, the following should hold for `int` being any integer value:
+
+```{spec IntSpec.intAddIncreases, int=allIntVals}
+int + 1 > int.
+self expect: int + 1 toBeKindOf: Integer.
+```
+
+And of course, we also expect the following to hold:
+
+```{spec IntSpec.intAddSymmetric, int=allIntVals, arg={allIntVals, allDoubleVals}}
+int + arg = (arg + int).
+self expect: int + arg toBeKindOf: arg class.
+```
+
+##### Subtraction
+
+Subtracting an arbitrary-precision integer from another returns an arbitrary-precision integer.
+
+For example:
+
+```{spec IntSpec.intSubtraction}
+ 4 - 3 =  1.
+-4 - 3 = -7.
+```
+
+Subtracting a `Double` from an integer results in a `Double` value.
+
+For example:
+```{spec IntSpec.doubleSubtraction}
+self expect:  4 - 3.3 toEqual:  0.7 within: 0.00000001.
+self expect: -4 - 3.5 toEqual: -7.5 within: 0.00000001.
+```
+
+Furthermore, the following should hold for `int` being any integer value:
+
+```{spec IntSpec.intSubDecrease, int=allIntVals}
+int - 1 < int.
+self expect: int - 1 toBeKindOf: Integer.
+```
+
+And of course, we also expect the following to hold:
+
+```{spec IntSpec.intSubAbsSymmetric, int=allIntVals, arg={allIntVals, allDoubleVals}}
+(int - arg) abs = (arg - int) abs.
+self expect: int - arg toBeKindOf: arg class.
+```
+
+
+[SOM]: http://www.hpi.uni-potsdam.de/hirschfeld/projects/som/
+[SOM-st]: https://som-st.github.io