From d1b5bc1f05624614f43ef85597f4aa9d7a166d23 Mon Sep 17 00:00:00 2001
From: Luke Shumaker <lukeshu@lukeshu.com>
Date: Sun, 29 Jan 2023 17:40:13 -0700
Subject: parse: Add an example of how the stack works for arrays, add tests

---
 internal/parse.go | 38 ++++++++++++++++++++++++++++++--------
 1 file changed, 30 insertions(+), 8 deletions(-)

(limited to 'internal/parse.go')

diff --git a/internal/parse.go b/internal/parse.go
index bb849e7..121857b 100644
--- a/internal/parse.go
+++ b/internal/parse.go
@@ -268,6 +268,8 @@ type Parser struct {
 	//
 	// Within each element type, the stack item is replaced, not pushed.
 	//
+	// (Keep each of these examples in-sync with parse_test.go.)
+	//
 	// For example, given the input string
 	//
 	//   {"x":"y","a":"b"}
@@ -293,9 +295,34 @@ type Parser struct {
 	//   o"      {"x":"y","a":"b
 	//   o       {"x":"y","a":"b"
 	//           {"x":"y","a":"b"}
+	//
+	// Or, given the input string
+	//
+	//   ["x","y"]
+	//
+	// The stack would be
+	//
+	//   stack   processed
+	//   ?
+	//   [       [
+	//   a"      ["
+	//   a"      ["x
+	//   a       ["x"
+	//   ]       ["x",
+	//   a"      ["x","
+	//   a"      ["x","y
+	//   a       ["x","y"
+	//           ["x","y"]
 	stack []RuneType
 }
 
+func (par *Parser) init() {
+	if !par.initialized {
+		par.initialized = true
+		par.pushState(runeTypeAny)
+	}
+}
+
 func (par *Parser) pushState(state RuneType) RuneType {
 	par.stack = append(par.stack, state)
 	return state
@@ -311,6 +338,7 @@ func (par *Parser) popState() {
 }
 
 func (par *Parser) stackString() string {
+	par.init()
 	var buf strings.Builder
 	for _, s := range par.stack {
 		buf.WriteString(s.String())
@@ -351,10 +379,7 @@ func (par *Parser) HandleEOF() (RuneType, error) {
 	if par.err != nil {
 		return RuneTypeError, par.err
 	}
-	if !par.initialized {
-		par.initialized = true
-		par.pushState(runeTypeAny)
-	}
+	par.init()
 	switch len(par.stack) {
 	case 0:
 		return RuneTypeEOF, nil
@@ -395,10 +420,7 @@ func (par *Parser) HandleRune(c rune) (RuneType, error) {
 	if par.err != nil {
 		return RuneTypeError, par.err
 	}
-	if !par.initialized {
-		par.initialized = true
-		par.pushState(runeTypeAny)
-	}
+	par.init()
 	if len(par.stack) == 0 {
 		switch c {
 		case 0x0020, 0x000A, 0x000D, 0x0009:
-- 
cgit v1.2.3-2-g168b


From 7de3be7d772ab32adb1a865450ba60567367064c Mon Sep 17 00:00:00 2001
From: Luke Shumaker <lukeshu@lukeshu.com>
Date: Mon, 30 Jan 2023 17:27:14 -0700
Subject: parse: Simplify the stack states for arrays

We already have a wildcard, no need to invent a new state.
---
 internal/parse.go | 14 ++------------
 1 file changed, 2 insertions(+), 12 deletions(-)

(limited to 'internal/parse.go')

diff --git a/internal/parse.go b/internal/parse.go
index 121857b..b11aae6 100644
--- a/internal/parse.go
+++ b/internal/parse.go
@@ -264,7 +264,6 @@ type Parser struct {
 	//
 	//   [   array: waiting for item to start or ']'
 	//   a   array: reading item / waiting for ',' or ']'
-	//   ]   array: waiting for item to start
 	//
 	// Within each element type, the stack item is replaced, not pushed.
 	//
@@ -308,7 +307,7 @@ type Parser struct {
 	//   a"      ["
 	//   a"      ["x
 	//   a       ["x"
-	//   ]       ["x",
+	//   a?      ["x",
 	//   a"      ["x","
 	//   a"      ["x","y
 	//   a       ["x","y"
@@ -513,21 +512,12 @@ func (par *Parser) HandleRune(c rune) (RuneType, error) {
 			par.pushState(runeTypeAny)
 			return par.HandleRune(c)
 		}
-	case RuneTypeArrayEnd: // waiting for item
-		switch c {
-		case 0x0020, 0x000A, 0x000D, 0x0009:
-			return RuneTypeSpace, nil
-		default:
-			par.replaceState(RuneTypeArrayComma)
-			par.pushState(runeTypeAny)
-			return par.HandleRune(c)
-		}
 	case RuneTypeArrayComma: // waiting for ',' or ']'
 		switch c {
 		case 0x0020, 0x000A, 0x000D, 0x0009:
 			return RuneTypeSpace, nil
 		case ',':
-			par.replaceState(RuneTypeArrayEnd)
+			par.pushState(runeTypeAny)
 			return RuneTypeArrayComma, nil
 		case ']':
 			par.popState()
-- 
cgit v1.2.3-2-g168b