add parseFileAnySyntax and parseResourceAnySyntax

To parse a basename.{conf,json,properties}

src/main/java/com/typesafe/config/ConfigFactory.java

@@ -141,12 +141,45 @@ public final class ConfigFactory {
         return Parseable.newFile(file, options).parse().toConfig();
     }
 
+    /**
+     * Parses a file. If the fileBasename already ends in a known extension,
+     * just parses it according to that extension. If the fileBasename does not
+     * end in an extension, then parse all known extensions and merge whatever
+     * is found. If options force a specific syntax, only parse files with an
+     * extension matching that syntax. If options.getAllowMissing() is true,
+     * then no files have to exist; if false, then at least one file has to
+     * exist.
+     *
+     * @param fileBasename
+     * @param options
+     * @return
+     */
+    public static Config parseFileAnySyntax(File fileBasename,
+            ConfigParseOptions options) {
+        return ConfigImpl.parseFileAnySyntax(fileBasename, options).toConfig();
+    }
+
     public static Config parseResource(Class<?> klass, String resource,
             ConfigParseOptions options) {
         return Parseable.newResource(klass, resource, options).parse()
                 .toConfig();
     }
 
+    /**
+     * Same behavior as parseFileAnySyntax() but for classpath resources
+     * instead.
+     *
+     * @param klass
+     * @param resourceBasename
+     * @param options
+     * @return
+     */
+    public static Config parseResourceAnySyntax(Class<?> klass, String resourceBasename,
+            ConfigParseOptions options) {
+        return ConfigImpl.parseResourceAnySyntax(klass, resourceBasename,
+                options).toConfig();
+    }
+
     public static Config parseString(String s, ConfigParseOptions options) {
         return Parseable.newString(s, options).parse().toConfig();
     }

src/main/java/com/typesafe/config/impl/ConfigImpl.java

@@ -1,5 +1,6 @@
 package com.typesafe.config.impl;
 
+import java.io.File;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
@@ -55,9 +56,10 @@ public class ConfigImpl {
         ConfigParseable nameToParseable(String name);
     }
 
-    // this function is a little tricky because there are two places we're
+    // this function is a little tricky because there are three places we're
-    // trying to use it; for 'include "basename"' in a .conf file, and for
+    // trying to use it; for 'include "basename"' in a .conf file, for
-    // loading app.{conf,json,properties} from classpath.
+    // loading app.{conf,json,properties} from classpath, and for
+    // loading app.{conf,json,properties} from the filesystem.
     private static ConfigObject fromBasename(NameSource source, String name,
             ConfigParseOptions options) {
         ConfigObject obj;
@@ -136,14 +138,31 @@ public class ConfigImpl {
             final ConfigParseOptions baseOptions) {
         Path path = Parser.parsePath(expression);
         String basename = makeResourceBasename(path);
+        return parseResourceAnySyntax(ConfigImpl.class, basename, baseOptions);
+    }
+
+    /** For use ONLY by library internals, DO NOT TOUCH not guaranteed ABI */
+    public static ConfigObject parseResourceAnySyntax(final Class<?> klass,
+            String resourceBasename, final ConfigParseOptions baseOptions) {
         NameSource source = new NameSource() {
             @Override
             public ConfigParseable nameToParseable(String name) {
-                return Parseable.newResource(ConfigImpl.class, name,
+                return Parseable.newResource(klass, name, baseOptions);
-                        baseOptions);
             }
         };
-        return fromBasename(source, basename, baseOptions);
+        return fromBasename(source, resourceBasename, baseOptions);
+    }
+
+    /** For use ONLY by library internals, DO NOT TOUCH not guaranteed ABI */
+    public static ConfigObject parseFileAnySyntax(final File basename,
+            final ConfigParseOptions baseOptions) {
+        NameSource source = new NameSource() {
+            @Override
+            public ConfigParseable nameToParseable(String name) {
+                return Parseable.newFile(new File(name), baseOptions);
+            }
+        };
+        return fromBasename(source, basename.getPath(), baseOptions);
     }
 
     /** For use ONLY by library internals, DO NOT TOUCH not guaranteed ABI */

src/test/scala/com/typesafe/config/impl/PublicApiTest.scala

@@ -321,4 +321,33 @@ class PublicApiTest extends TestUtils {
         assertEquals(List("letters/a.conf", "numbers/1.conf", "numbers/2", "letters/b.json", "letters/c"),
             included.map(_.name))
     }
+
+    @Test
+    def anySyntax() {
+        // test01 has all three syntaxes; first load with basename
+        val conf = ConfigFactory.parseFileAnySyntax(resourceFile("test01"), ConfigParseOptions.defaults())
+        assertEquals(42, conf.getInt("ints.fortyTwo"))
+        assertEquals("A", conf.getString("fromJsonA"))
+        assertEquals("true", conf.getString("fromProps.bool"))
+
+        // now include a suffix, should only load one of them
+        val onlyProps = ConfigFactory.parseFileAnySyntax(resourceFile("test01.properties"), ConfigParseOptions.defaults())
+        assertFalse(onlyProps.hasPath("ints.fortyTwo"))
+        assertFalse(onlyProps.hasPath("fromJsonA"))
+        assertEquals("true", onlyProps.getString("fromProps.bool"))
+
+        // force only one syntax via options
+        val onlyPropsViaOptions = ConfigFactory.parseFileAnySyntax(resourceFile("test01.properties"),
+            ConfigParseOptions.defaults().setSyntax(ConfigSyntax.PROPERTIES))
+        assertFalse(onlyPropsViaOptions.hasPath("ints.fortyTwo"))
+        assertFalse(onlyPropsViaOptions.hasPath("fromJsonA"))
+        assertEquals("true", onlyPropsViaOptions.getString("fromProps.bool"))
+
+        // make sure it works with resources too
+        val fromResources = ConfigFactory.parseResourceAnySyntax(classOf[PublicApiTest], "/test01",
+            ConfigParseOptions.defaults())
+        assertEquals(42, fromResources.getInt("ints.fortyTwo"))
+        assertEquals("A", fromResources.getString("fromJsonA"))
+        assertEquals("true", fromResources.getString("fromProps.bool"))
+    }
 }