Bugfix/issue 70

pom.xml

@@ -104,6 +104,11 @@
             <artifactId>web3j-sokt</artifactId>
             <version>0.2.1</version>
         </dependency>
+        <dependency>
+            <groupId>com.github.zafarkhaja</groupId>
+            <artifactId>java-semver</artifactId>
+            <version>0.9.0</version>
+        </dependency>
 
     </dependencies>
 

src/main/java/org/web3j/mavenplugin/solidity/SolidityCompiler.java

@@ -1,16 +1,14 @@
 package org.web3j.mavenplugin.solidity;
 
+import com.github.zafarkhaja.semver.Version;
 import org.apache.maven.plugin.logging.Log;
 import org.web3j.sokt.SolcInstance;
 import org.web3j.sokt.SolidityFile;
+import org.web3j.tuples.generated.Tuple2;
 
 import java.io.*;
 import java.nio.file.Paths;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.Collection;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
@@ -23,6 +21,9 @@ public class SolidityCompiler {
 
     private Log LOG;
 
+    private static final String LOWEST_PRAGMA_VERSION = "0.0.0";
+    private static final String HIGHEST_PRAGMA_VERSION = "1000.1000.1000";
+
     private static SolidityCompiler INSTANCE;
     private String usedSolCVersion;
 
@@ -73,7 +74,7 @@ public CompilerResult compileSrc(
     }
 
     private Process getSolcProcessFromSokt(String rootDirectory, Collection<String> sources, String[] pathPrefixes, Options[] options) throws IOException {
-        SolidityFile solidityFile = new SolidityFile(Paths.get(rootDirectory, sources.iterator().next()).toFile().getAbsolutePath());
+        SolidityFile solidityFile = checkPragmaVersions(rootDirectory, sources);
         SolcInstance instance = solidityFile.getCompilerInstance(".web3j", true);
         if (!instance.installed()) instance.install();
         usedSolCVersion = instance.getSolcRelease().getVersion();
@@ -83,6 +84,72 @@ private Process getSolcProcessFromSokt(String rootDirectory, Collection<String>
         return process;
     }
 
+    private SolidityFile checkPragmaVersions(String rootDirectory, Collection<String> sources) {
+        SolidityFile solidityFile = null;
+        if (sources != null) {
+             solidityFile = findMinAndMaxPragma(rootDirectory, sources);
+        }
+        return solidityFile;
+    }
+
+    //narrow down solidity versions to the most common
+    private SolidityFile findMinAndMaxPragma(String rootDirectory, Collection<String> sources) {
+        Version minVersion = Version.valueOf(LOWEST_PRAGMA_VERSION);
+        Version maxVersion = Version.valueOf(HIGHEST_PRAGMA_VERSION);
+        SolidityFile selectedSolidityFile = null;
+        for (String source : sources) {
+            SolidityFile solidityFile = new SolidityFile(Paths.get(rootDirectory, source).toFile().getAbsolutePath());
+            Tuple2<Version,Version> minMaxTuple = getCurrentVersion(rootDirectory, solidityFile);
+            Version minCurrentVersion = minMaxTuple.component1();
+            Version maxCurrentVersion = minMaxTuple.component2();
+            boolean changedMin = false;
+            boolean changedMax = false;
+            if (minCurrentVersion.greaterThanOrEqualTo(minVersion)) {
+                minVersion = minCurrentVersion;
+                changedMin = true;
+            }
+            if (maxCurrentVersion.lessThanOrEqualTo(maxVersion)) {
+                maxVersion = maxCurrentVersion;
+                changedMax = true;
+            }
+            if (changedMin && changedMax) {
+                selectedSolidityFile = solidityFile;
+            }
+        }
+        if ((minVersion.greaterThan(maxVersion))) {
+            throw new RuntimeException("There are some contracts that have higher lowest pragma version then the highest pragma versions of other contracts.");
+        }
+        return selectedSolidityFile;
+    }
+
+    private Tuple2<Version, Version> getCurrentVersion(String rootDirectory, SolidityFile solidityFile) {
+        Version minCurrentVersion;
+        Version maxCurrentVersion;
+        String[] versions = cutVersionOperator(solidityFile.getVersionPragma()).replace(";","").split(" ");
+        if (versions.length == 1) {
+            minCurrentVersion = Version.valueOf(versions[0]);
+            maxCurrentVersion = Version.forIntegers(minCurrentVersion.getMajorVersion(), minCurrentVersion.getMinorVersion() + 1, minCurrentVersion.getPatchVersion());
+        } else {
+            Version firstVersion = Version.valueOf(versions[0]);
+            Version secondVersion = Version.valueOf(versions[1]);
+            if (firstVersion.greaterThan(secondVersion)) {
+                minCurrentVersion = secondVersion;
+                maxCurrentVersion = firstVersion;
+            } else {
+                minCurrentVersion = firstVersion;
+                maxCurrentVersion = secondVersion;
+            }
+        }
+        return new Tuple2<>(minCurrentVersion, maxCurrentVersion);
+    }
+
+    private String cutVersionOperator(String version) {
+        return version.replace(">", "")
+                .replace("<", "")
+                .replace("=", "")
+                .replace("^", "");
+    }
+
     private Map<String, String> getAbsolutePathPrefixes(String rootDirectory, String[] pathPrefixes) {
         return Stream.of(pathPrefixes)
                 .map(pathPrefix -> replaceMakePathPrefixAbsolute(rootDirectory, pathPrefix))
@@ -132,8 +199,7 @@ public enum Options {
         BIN("bin"),
         INTERFACE("interface"),
         ABI("abi"),
-        METADATA("metadata")
-        ;
+        METADATA("metadata");
 
         private final String name;
 

src/test/java/org/web3j/mavenplugin/solidity/SolidityCompilerTest.java

@@ -1,11 +1,16 @@
 package org.web3j.mavenplugin.solidity;
 
+import org.apache.commons.io.FileUtils;
 import org.apache.maven.plugin.MojoExecutionException;
 import org.apache.maven.plugin.logging.SystemStreamLog;
 import org.junit.Before;
 import org.junit.Test;
 
+import java.io.IOException;
+import java.nio.file.Paths;
 import java.util.Collections;
+import java.util.LinkedList;
+import java.util.List;
 import java.util.Set;
 
 import static org.hamcrest.CoreMatchers.containsString;
@@ -65,6 +70,23 @@ public void pragmaVersionTooHigh() {
         }
     }
 
+    @Test
+    public void differentPragmas() {
+        //delete /home/$user/.web3j folder to download evrerytime (fresh install) new solc version
+        String currentUsersHomeDir = System.getProperty("user.home");
+        try {
+            FileUtils.deleteDirectory(Paths.get(currentUsersHomeDir + "/.web3j").toFile());
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+        List<String> source = new LinkedList<>();
+        //it will download 0.6.12 version
+        source.add("File2.sol");
+        source.add("File1.sol");
+        CompilerResult result = solidityCompiler.compileSrc("src/test/resources/issue-70", source, new String[0], SolidityCompiler.Options.ABI, SolidityCompiler.Options.BIN);
+        assertTrue(result.errors.isEmpty());
+    }
+
     @Before
     public void loadCompiler() throws MojoExecutionException {
         solidityCompiler = SolidityCompiler.getInstance(new SystemStreamLog());

src/test/resources/issue-70/File1.sol

@@ -0,0 +1,5 @@
+pragma solidity >=0.5.0 <0.6.0;
+
+contract File1 {
+
+}

src/test/resources/issue-70/File2.sol

@@ -0,0 +1,5 @@
+pragma solidity >=0.5.0 <0.7.0;
+
+contract File2 {
+
+}