resolves #394 fix gem requirements resolution

Author: ggrossetie

base-plugin/src/integTest/groovy/com/github/jrubygradle/JRubyPrepareGemsIntegrationSpec.groovy

@@ -76,6 +76,27 @@ class JRubyPrepareGemsIntegrationSpec extends IntegrationSpecification {
         new File(projectDir, "gems/rack-1.6.12").exists()
     }
 
+    @IgnoreIf({ IntegrationSpecification.OFFLINE })
+    void "Check if selenium-webdriver version gets resolved"() {
+        setup:
+        withPreamble """repositories.ruby.gems()
+            jrubyPrepare.outputDir = '${pathAsUriStr(projectDir)}'.toURI()
+        """
+
+        withDependencies """
+            gems 'rubygems:selenium-webdriver:3.142.6'
+            gems 'rubygems:webdrivers:4.1.3'
+        """
+
+        when:
+        build()
+
+        then:
+        // since we need a version range in the setup the
+        // resolved version here can vary over time
+        new File(projectDir, "gems/selenium-webdriver-3.142.6").exists()
+    }
+
     @IgnoreIf({ IntegrationSpecification.OFFLINE })
     void "Check that GEM dependencies are locked"() {
         setup:

core-plugin/src/main/groovy/com/github/jrubygradle/api/gems/GemVersion.groovy

@@ -177,7 +177,7 @@ class GemVersion implements Comparable<GemVersion> {
             gemVersions.first()
         } else {
             gemVersions[1..-1].inject(gemVersions.first()) { range, value ->
-                range.union(value)
+                range.intersect(value)
             }
         }
     }
@@ -300,66 +300,53 @@ class GemVersion implements Comparable<GemVersion> {
      * @since 2.0
      */
     GemVersion intersect(GemVersion other) {
-        Boundary newLowBoundary
-        String newLow
-        switch (compare(low, other.low)) {
-            case -1:
-                newLow = other.low
-                newLowBoundary = other.lowBoundary
-                break
-            case 0:
-                newLowBoundary = (lowBoundary == EXCLUSIVE || other.lowBoundary == EXCLUSIVE) ? EXCLUSIVE : INCLUSIVE
-                newLow = low
-                break
-            case 1:
-                newLow = low
-                newLowBoundary = lowBoundary
+        Tuple2<String, Boundary> newLowVersionSpec = intersect(low, lowBoundary, other.low, other.lowBoundary, true)
+        Tuple2<String, Boundary> newHighVersionSpec = intersect(high, highBoundary, other.high, other.highBoundary, false)
+        GemVersion intersection = new GemVersion(newLowVersionSpec.second, newLowVersionSpec.first, newHighVersionSpec.first, newHighVersionSpec.second)
+        if (intersection == this) {
+            // is other a subset of this?
+            if (compare(this.low, other.low) >= 0 && compare(other.low, this.high) < 0 && compare(this.high, other.high) <= 0) {
+                return intersection
+            }
+            return NO_VERSION
         }
-
-        Boundary newHighBoundary
-        String newHigh
-
-        if (!high && other.high) {
-            newHigh = other.high
-            newHighBoundary = other.highBoundary
-        } else if (high && !other.high) {
-            newHigh = high
-            newHighBoundary = highBoundary
-        } else if (!high && !other.high) {
-            newHigh = null
-            newHighBoundary = highBoundary
-        } else {
-            switch (compare(high, other.high)) {
-                case 1:
-                    newHigh = other.high
-                    newHighBoundary = other.highBoundary
-                    break
-                case 0:
-                    newHighBoundary = (highBoundary == EXCLUSIVE || other.highBoundary == EXCLUSIVE) ? EXCLUSIVE : INCLUSIVE
-                    newHigh = high
-                    break
-                case -1:
-                    newHigh = high
-                    newHighBoundary = highBoundary
+        if (intersection == other) {
+            // is this a subset of other?
+            if (compare(other.low, this.low) >= 0 && compare(this.low, other.high) < 0 && compare(other.high, this.high) <= 0) {
+                return intersection
             }
+            return NO_VERSION
         }
-        return new GemVersion(newLowBoundary, newLow, newHigh, newHighBoundary)
+        return intersection
     }
 
-    /** Creates a new GEM version requirement which that the lowest of two requirements and the highest
-     * of those same requirement
-     *
-     * @param other Other GEM to combine with
-     * @return New GEM version requirement.
-     *
-     * @since 2.0
-     */
-    GemVersion union(GemVersion other) {
-        List<GemVersion> pair = [this, other]
-        GemVersion min = pair.min()
-        GemVersion max = pair.max()
+    Tuple2<String,Boundary> intersect(String version, Boundary boundary, String otherVersion, Boundary otherBoundary, boolean low) {
+        Boundary newBoundary
+        String newVersion
+        if (!version && otherVersion) {
+            newVersion = otherVersion
+            newBoundary = otherBoundary
+        } else if (version && !otherVersion) {
+            newVersion = version
+            newBoundary = boundary
+        } else if (!version && !otherVersion) {
+            newVersion = null
+            newBoundary = boundary
+        } else {
+            int compareLow = low ? compare(version, otherVersion) : compare(otherVersion, version)
+            if (compareLow < 0) {
+                newVersion = otherVersion
+                newBoundary = otherBoundary
+            } else if (compareLow > 0) {
+                newVersion = version
+                newBoundary = boundary
+            } else {
+                newBoundary = (boundary == INCLUSIVE || otherBoundary == INCLUSIVE) ? INCLUSIVE : EXCLUSIVE
+                newVersion = version
+            }
+        }
 
-        new GemVersion(min.lowBoundary, min.low, max.high, max.highBoundary)
+        return new Tuple2(newVersion, newBoundary)
     }
 
     /** Allows for versions to be compared and sorted.

core-plugin/src/test/groovy/com/github/jrubygradle/api/gems/GemVersionSpec.groovy

@@ -23,7 +23,6 @@
  */
 package com.github.jrubygradle.api.gems
 
-import com.github.jrubygradle.api.gems.GemVersion
 import spock.lang.Specification
 import spock.lang.Unroll
 
@@ -77,7 +76,7 @@ class GemVersionSpec extends Specification {
     }
 
     @Unroll
-    void "Intersect: #ivyLeft ∩ #ivyRight ⇒ Gem #gemVer"() {
+    void "intersect: #ivyLeft ∩ #ivyRight ⇒ Gem #gemVer"() {
         when:
         GemVersion lhs = gemVersionFromGradleIvyRequirement(ivyLeft)
         GemVersion rhs = gemVersionFromGradleIvyRequirement(ivyRight)
@@ -87,10 +86,10 @@ class GemVersionSpec extends Specification {
 
         where:
         ivyLeft             | ivyRight            | gemVer
-        '[1.2.1,1.2.4]'     | ']1.2.1,1.2.4['     | ']1.2.1,1.2.4['
+        '[1.2.1,1.2.4]'     | ']1.2.1,1.2.4['     | '[1.2.1,1.2.4]'
         '[1.2.0,1.2.4]'     | ']1.2.1,1.2.3['     | ']1.2.1,1.2.3['
         '[1.2.0,1.2.4]'     | '[1.2.1,1.2.3]'     | '[1.2.1,1.2.3]'
-        ']1.2.0,1.2.4['     | '[1.2.0,1.2.4]'     | ']1.2.0,1.2.4['
+        ']1.2.0,1.2.4['     | '[1.2.0,1.2.4]'     | '[1.2.0,1.2.4]'
         ']1.2.1,1.2.3['     | '[1.2.0,1.2.4]'     | ']1.2.1,1.2.3['
         '[1.2.1,1.2.3]'     | '[1.2.0,1.2.4]'     | '[1.2.1,1.2.3]'
         '[1.2.10,1.2.14]'   | '[1.2.2,1.10.14]'   | '[1.2.10,1.2.14]'
@@ -100,17 +99,28 @@ class GemVersionSpec extends Specification {
         ']2.5.1.1,99999]'   | ']2.5.1.1,)'        | ']2.5.1.1,99999]'
     }
 
-    void 'Ivy union of < 3, >= 1.2'() {
-        expect:
-        singleGemVersionFromMultipleGemRequirements('< 3,>= 1.2').toString() == '[1.2,3['
+    @Unroll
+    void '#gemRequirements (requirements) ⇒ #gemRequirement (requirement)'() {
+        when:
+        GemVersion subject = singleGemVersionFromMultipleGemRequirements(gemRequirements)
+
+        then:
+        subject.toString() == gemRequirement
+
+        where:
+        gemRequirements    | gemRequirement
+        '< 3,>= 1.2'       | '[1.2,3['
+        '>= 3.0, < 4.0'    | '[3.0,4.0['
+        '< 4.0, >= 3.0'    | '[3.0,4.0['
+        '~> 2.2, >= 2.2.1' | '[2.2.1,3.0['
     }
 
     void "intersects with conflict"() {
         given:
         GemVersion subject = gemVersionFromGradleIvyRequirement('[1.2.1,1.2.3]')
 
         expect:
-        subject.intersect('[1.2.4, 1.2.4]').conflict() == true
+        subject.intersect('[1.2.4, 1.2.4]').conflict()
     }
 
     void "finds no conflicts in non-integer version ranges"() {