Added folding support for functions and macro definitions.

build.gradle

@@ -66,6 +66,7 @@ patchPluginXml {
     <li>New: Added semantic highlighting. Currently available for data and address registers and local labels.
     <li>Bugfix: addq/subq for address register stated it would affect the condition codes, which it in fact doesn't.
     <li>New: Added simple custom navigation bar.
+    <li>New: Added folding support for functions and macro definitions.
     </ul>
   <p>Full changelog available at <a href="https://github.com/chrisly42/mc68000-asm-plugin#changelog">Github project site</a>.</p>
 """)

src/main/java/de/platon42/intellij/plugins/m68k/folding/M68kFoldingBuilder.kt

@@ -0,0 +1,67 @@
+package de.platon42.intellij.plugins.m68k.folding
+
+import com.intellij.lang.ASTNode
+import com.intellij.lang.folding.FoldingBuilderEx
+import com.intellij.lang.folding.FoldingDescriptor
+import com.intellij.openapi.editor.Document
+import com.intellij.openapi.project.DumbAware
+import com.intellij.psi.PsiElement
+import com.intellij.psi.util.PsiTreeUtil
+import com.intellij.refactoring.suggested.endOffset
+import com.intellij.refactoring.suggested.startOffset
+import de.platon42.intellij.plugins.m68k.psi.M68kFile
+import de.platon42.intellij.plugins.m68k.psi.M68kMacroDefinition
+import de.platon42.intellij.plugins.m68k.psi.M68kStatement
+import de.platon42.intellij.plugins.m68k.psi.utils.M68kPsiWalkUtil.getBeginningOfRelatedComment
+import de.platon42.intellij.plugins.m68k.psi.utils.M68kPsiWalkUtil.isSignificantLine
+
+class M68kFoldingBuilder : FoldingBuilderEx(), DumbAware {
+
+    override fun buildFoldRegions(root: PsiElement, document: Document, quick: Boolean): Array<FoldingDescriptor> {
+        if (root !is M68kFile) return FoldingDescriptor.EMPTY
+
+        val descriptors = ArrayList<FoldingDescriptor>()
+        var lineElement = root.firstChild
+        var foldingOpen = false
+        var foldingStart: PsiElement? = null
+        var foldingName: String? = null
+        var lastStatement = lineElement as? M68kStatement
+        while (lineElement != null) {
+            if (lineElement is M68kMacroDefinition) {
+                val fd = FoldingDescriptor(lineElement, lineElement.startOffset, lineElement.endOffset, null, "[[[ MACRO " + lineElement.name!! + " ]]]")
+                descriptors.add(fd)
+            }
+            if (lineElement is M68kStatement) {
+                val label = lineElement.globalLabel
+                if (label != null) {
+                    foldingOpen = true
+                    foldingStart = getBeginningOfRelatedComment(lineElement)
+                    foldingName = "[[[ ${label.name} ]]]"
+                }
+                lastStatement = lineElement
+            }
+            lineElement = PsiTreeUtil.skipWhitespacesAndCommentsForward(lineElement)
+            if (foldingOpen) {
+                val stopIt = (lineElement == null) || isSignificantLine(lineElement)
+                if (stopIt) {
+                    val fd = FoldingDescriptor(
+                        foldingStart!!.parent!!,
+                        foldingStart.startOffsetInParent, lastStatement!!.textRangeInParent.endOffset,
+                        null, foldingName!!
+                    )
+                    descriptors.add(fd)
+                    foldingOpen = false
+                }
+            }
+        }
+        return descriptors.toArray(FoldingDescriptor.EMPTY)
+    }
+
+    override fun getPlaceholderText(node: ASTNode): String? {
+        return "..."
+    }
+
+    override fun isCollapsedByDefault(node: ASTNode): Boolean {
+        return false
+    }
+}

src/main/java/de/platon42/intellij/plugins/m68k/psi/utils/M68kPsiWalkUtil.kt

@@ -2,6 +2,7 @@ package de.platon42.intellij.plugins.m68k.psi.utils
 
 import com.intellij.psi.PsiComment
 import com.intellij.psi.PsiElement
+import com.intellij.psi.PsiWhiteSpace
 import com.intellij.psi.util.PsiTreeUtil
 import com.intellij.util.SmartList
 import com.intellij.util.containers.addIfNotNull
@@ -31,6 +32,31 @@ object M68kPsiWalkUtil {
         return comments.reversed()
     }
 
+    fun getBeginningOfRelatedComment(lineElement: PsiElement): PsiElement {
+        // go back to catch comments that are not more than one empty line away
+        var relStart = lineElement
+        var prevLine = relStart.prevSibling ?: return lineElement
+        var eolCount = 2
+        do {
+            if (prevLine is PsiComment) {
+                relStart = prevLine
+                eolCount = 1
+            } else if (prevLine is PsiWhiteSpace) {
+                if (--eolCount < 0) break
+            } else {
+                break
+            }
+            prevLine = prevLine.prevSibling ?: break
+        } while (true)
+        return relStart
+    }
+
+    fun isSignificantLine(element: PsiElement) = when (element) {
+        is M68kStatement -> (element.assignment != null) || (element.globalLabel != null)
+        is M68kMacroDefinition -> true
+        else -> false
+    }
+
     fun findStatementForElement(psiElement: PsiElement): M68kStatement? {
         if (psiElement is M68kStatement) return psiElement
         if (psiElement.parent is M68kFile) {

src/main/resources/META-INF/plugin.xml

@@ -21,6 +21,9 @@
                                implementationClass="de.platon42.intellij.plugins.m68k.parser.M68kParserDefinition"/>
         <lang.syntaxHighlighterFactory language="MC68000"
                                        implementationClass="de.platon42.intellij.plugins.m68k.syntax.M68kSyntaxHighlighterFactory"/>
+        <lang.foldingBuilder
+                language="MC68000"
+                implementationClass="de.platon42.intellij.plugins.m68k.folding.M68kFoldingBuilder"/>
         <navbar implementation="de.platon42.intellij.plugins.m68k.navigation.M68kStructureAwareNavbar"/>
         <highlightVisitor implementation="de.platon42.intellij.plugins.m68k.syntax.M68kRainbowVisitor"/>
         <colorSettingsPage implementation="de.platon42.intellij.plugins.m68k.syntax.M68kColorSettingsPage"/>

src/test/java/de/platon42/intellij/plugins/m68k/folding/M68kFoldingBuilderTest.kt

@@ -0,0 +1,19 @@
+package de.platon42.intellij.plugins.m68k.folding
+
+import com.intellij.testFramework.fixtures.CodeInsightTestFixture
+import de.platon42.intellij.jupiter.LightCodeInsightExtension
+import de.platon42.intellij.jupiter.MyFixture
+import de.platon42.intellij.jupiter.TestDataPath
+import org.junit.jupiter.api.Assertions.*
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.extension.ExtendWith
+
+@TestDataPath("src/test/resources/folding")
+@ExtendWith(LightCodeInsightExtension::class)
+internal class M68kFoldingBuilderTest {
+
+    @Test
+    internal fun check_documentation_for_a_symbol_definition(@MyFixture myFixture: CodeInsightTestFixture) {
+        myFixture.testFolding(myFixture.testDataPath + "/folding.asm")
+    }
+}

src/test/resources/folding/folding.asm

@@ -0,0 +1,46 @@
+; this is a test
+
+FOO = 1
+<fold text='[[[ demo_main ]]]'>; this is the main demo routine
+demo_main:
+        moveq.l #0,d0
+        rts
+
+; data area starts here
+.data   dc.w    10,0
+        even</fold>
+
+; this is an unrelated comment
+
+<fold text='[[[ intro_part1 ]]]'>; this is another folding area
+; could be anything.
+
+intro_part1
+        dc.w    $47fe
+        illegal
+        rts</fold>
+
+; this comment is two lines away
+
+
+<fold text='[[[ intro_part2 ]]]'>intro_part2:
+        moveq.l #0,d1
+        rts</fold>
+
+; standard macros
+<fold text='[[[ MACRO BLTWAIT ]]]'>BLTWAIT MACRO
+.bw\@
+        btst	#DMAB_BLTDONE-8,dmaconr(a5)
+        bne.s	.bw\@
+        ENDM</fold>
+
+********************** foobar
+
+
+<fold text='[[[ some_more_data ]]]'>some_more_data:
+        dc.w    $123
+        dc.w    $345
+        dc.w    $333
+        dc.w    $222</fold>
+
+CUBE_SIZE = 100