| Conditions | 10 | 
| Total Lines | 138 | 
| Code Lines | 107 | 
| Lines | 0 | 
| Ratio | 0 % | 
| Changes | 0 | ||
Small methods make your code easier to understand, in particular if combined with a good name. Besides, if your method is small, finding a good name is usually much easier.
For example, if you find yourself adding comments to a method's body, this is usually a good sign to extract the commented part to a new method, and use the comment as a starting point when coming up with a good name for this new method.
Commonly applied refactorings include:
If many parameters/temporary variables are present:
Complex classes like HillChart.renderGroup often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
| 1 | import EventEmitter from 'event-emitter-es6';  | 
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| 185 | |||
| 186 |   renderGroup() { | 
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| 187 | const self = this;  | 
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| 188 | |||
| 189 | // Handle dragging  | 
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| 190 | const dragPoint = drag<SVGGElement, DataPointInternal>()  | 
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| 191 |       .on('drag', function (data) { | 
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| 192 |         let { x } = event; | 
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| 193 | |||
| 194 | // Check point movement, preventing it from wondering outside the main curve  | 
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| 195 |         if (!x || x < 0) { | 
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| 196 | x = 0;  | 
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| 197 |           self.emit('home', { | 
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| 198 | ...data,  | 
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| 199 | y: hillFnInverse(self.yScale.invert(data.y)),  | 
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| 200 | });  | 
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| 201 |         } else if (x > self.chartWidth) { | 
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| 202 | x = self.chartWidth;  | 
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| 203 |           self.emit('end', { | 
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| 204 | ...data,  | 
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| 205 | x: self.xScale.invert(self.chartWidth),  | 
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| 206 | y: hillFnInverse(self.yScale.invert(data.y)),  | 
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| 207 | });  | 
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| 208 | }  | 
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| 209 | |||
| 210 | // Convert current point coordinates back to the original  | 
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| 211 | // between 0 and 100 to set it in the data attribute  | 
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| 212 | const invertedX = self.xScale.invert(x);  | 
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| 213 | |||
| 214 | data.x = x;  | 
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| 215 | |||
| 216 | data.y = self.yScale(hillFn(invertedX));  | 
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| 217 | |||
| 218 | const invertedY = hillFnInverse(self.yScale.invert(data.y));  | 
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| 219 | |||
| 220 |         const newInvertedCoordinates = { | 
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| 221 | x: invertedX,  | 
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| 222 | y: invertedY,  | 
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| 223 | };  | 
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| 224 | |||
| 225 | // click event  | 
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| 226 |         select<SVGGElement, DataPointInternal>(this).on('click', () => { | 
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| 227 |           self.emit('pointClick', { ...data, ...newInvertedCoordinates }); | 
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| 228 | });  | 
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| 229 | |||
| 230 |         if (!self.preview) { | 
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| 231 | const selectedPoint = select<SVGGElement, DataPointInternal>(  | 
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| 232 | this  | 
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| 233 |           ).attr('transform', `translate(${data.x}, ${data.y})`); | 
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| 234 | selectedPoint  | 
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| 235 |             .select('text') | 
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| 236 |             .style('text-anchor', () => { | 
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| 237 |               if (textOutRange(invertedX)) { | 
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| 238 | return 'end';  | 
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| 239 | }  | 
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| 240 | return 'start';  | 
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| 241 | })  | 
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| 242 |             .attr('x', (point) => | 
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| 243 | calculateTextPositionForX(point.size, invertedX)  | 
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| 244 | );  | 
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| 245 | |||
| 246 |           self.emit('move', invertedX, invertedY); | 
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| 247 | }  | 
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| 248 | })  | 
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| 249 |       .on('end', (data) => { | 
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| 250 |         if (this.preview) { | 
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| 251 | return;  | 
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| 252 | }  | 
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| 253 | |||
| 254 |         let { x } = event; | 
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| 255 | |||
| 256 | // Check point movement, preventing it from wondering outside the main curve  | 
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| 257 |         if (!x || x < 0) { | 
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| 258 | x = 0;  | 
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| 259 |         } else if (x > this.chartWidth) { | 
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| 260 | x = this.chartWidth;  | 
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| 261 | }  | 
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| 262 | |||
| 263 | // Convert current point coordinates back to the original  | 
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| 264 | const invertedX = this.xScale.invert(x);  | 
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| 265 | data.y = this.yScale(hillFn(invertedX));  | 
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| 266 | const invertedY = hillFnInverse(this.yScale.invert(data.y));  | 
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| 267 | |||
| 268 |         const newInvertedCoordinates = { | 
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| 269 | x: invertedX,  | 
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| 270 | y: invertedY,  | 
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| 271 | };  | 
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| 272 | |||
| 273 |         this.emit('moved', { ...data, ...newInvertedCoordinates }); | 
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| 274 | });  | 
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| 275 | |||
| 276 | let group:  | 
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| 277 | | Selection<SVGGElement, DataPointInternal, SVGGElement, unknown>  | 
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| 278 | | undefined;  | 
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| 279 | |||
| 280 |     if (this.preview) { | 
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| 281 | group = this.undraggablePoint();  | 
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| 282 |     } else { | 
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| 283 | // Create group consisted of a circle and a description text, where  | 
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| 284 | // the data attributes determine the position of them on the curve  | 
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| 285 | group = this.svg  | 
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| 286 |         .selectAll('.hill-chart-group') | 
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| 287 | .data(this.data)  | 
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| 288 | .enter()  | 
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| 289 |         .append('g') | 
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| 290 |         .attr('class', 'hill-chart-group') | 
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| 291 |         .attr('transform', (data) => { | 
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| 292 | data.x = this.xScale(data.x);  | 
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| 293 | data.y = this.yScale(data.y);  | 
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| 294 |           return `translate(${data.x}, ${data.y})`; | 
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| 295 | })  | 
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| 296 | .call(dragPoint);  | 
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| 297 | }  | 
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| 298 | |||
| 299 | group  | 
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| 300 |       .append('circle') | 
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| 301 |       .attr('class', 'hill-chart-circle') | 
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| 302 |       .attr('fill', (data) => data.color) | 
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| 303 |       .attr('cx', 0) | 
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| 304 |       .attr('cy', 0) | 
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| 305 |       .attr('r', (data) => data.size || DEFAULT_SIZE); | 
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| 306 | |||
| 307 | group  | 
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| 308 |       .append('text') | 
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| 309 | .text((data) => data.description)  | 
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| 310 |       .attr('x', (data) => | 
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| 311 | calculateTextPositionForX(  | 
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| 312 | data.size || DEFAULT_SIZE,  | 
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| 313 | this.xScale.invert(data.x)  | 
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| 314 | )  | 
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| 315 | )  | 
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| 316 |       .style('text-anchor', (data) => { | 
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| 317 |         if (textOutRange(this.xScale.invert(data.x))) { | 
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| 318 | return 'end';  | 
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| 319 | }  | 
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| 320 | return 'start';  | 
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| 321 | })  | 
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| 322 |       .attr('y', calculateTextMarginForY()); | 
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| 323 | }  | 
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| 385 |